fix(fxrt): tang cushion worklet 128->256ms + telemetry underrun (giam crackle do main-thread stall)

app/static/js/app.jsx

@@ -1767,7 +1767,7 @@ async function fxRtStart() {
   fxRt.sessionId = st.session_id;
   fxRtGuiPushShm();
   try {
-    await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608241900`);
+    await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608242000`);
     if (token !== fxRt.startToken) { fxRt.starting = false; return; }
     fxRt.node = new AudioWorkletNode(ctx, 'sf-fx-realtime', { numberOfInputs: 1, numberOfOutputs: 1, outputChannelCount: [2] });
     const u = new URL(API_BASE_URL);
@@ -1861,6 +1861,12 @@ async function fxRtStart() {
         try { fxRt.ws.send(JSON.stringify({ cmd: 'set_param', slot: d.slot, key: d.key, value: d.value })); } catch (e) {}
         return;
       }
+      if (d.type === 'stats') {
+        // Telemetry worklet (mỗi ~2s): chẩn đoán crackle session thật.
+        fxRt.stats = d;
+        console.debug('[FX RT stats]', d);
+        return;
+      }
       if (d.type !== 'in') return;
       fxRt.inQueue.push(d);
       fxRtInPump();
@@ -23839,7 +23845,7 @@ const App = () => {
     fxRtTracks[key] = entry;
     fxRtGuiPushShm();
     try {
-      await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608241900`);
+      await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608242000`);
       const node = new AudioWorkletNode(ctx, 'sf-fx-realtime', { numberOfInputs: 1, numberOfOutputs: 1, outputChannelCount: [2] });
       entry.node = node;
       const u = new URL(API_BASE_URL);

app/static/js/app.precompiled.js

@@ -304,7 +304,7 @@ else if(fxRt.chainKey!==ck){fxRtSetChain(chain);fxRt.chainKey=ck;return;}else re
 // node → bypass vô hiệu. Mỗi fxRtStop() bump startToken → mọi checkpoint
 // dưới đây thấy mismatch → hủy session vừa tạo, không nối node.
 const token=++fxRt.startToken;fxRt.starting=true;const ctx=getAudioContext();if(!ctx||!ctx.audioWorklet||!masterBus||!masterBus.output||!masterBus.analyser||!masterBus.masterFxGain||!masterBus.masterFxDryGain)return;const chainPayload=chain.map(s=>s.type==='vst3'?{type:'vst3',path:s.path,name:s.name||s.path,preset_b64:s.preset_b64||'',bypass:false}:{type:'builtin',id:s.type,params:s.params&&Object.keys(s.params).length?s.params:{},bypass:false});let st;try{st=await window.SonicAPI.fxRealtimeStart({fx_chain:chainPayload,sample_rate:ctx.sampleRate||44100});}catch(e){console.warn('[FX RT] start fail:',e);showToast('Không khởi động VST FX realtime: '+(e.message||e),'warning');fxRt.starting=false;return;}if(token!==fxRt.startToken){// Bypass/stop giữa lúc engine đang load chain — hủy session vừa tạo.
-console.warn('[FX RT] start cancelled mid-flight — session stopped');try{window.SonicAPI.fxRealtimeStop({session_id:st.session_id}).catch(()=>{});}catch(e2){}fxRt.starting=false;return;}fxRt.sessionId=st.session_id;fxRtGuiPushShm();try{await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608241900`);if(token!==fxRt.startToken){fxRt.starting=false;return;}fxRt.node=new AudioWorkletNode(ctx,'sf-fx-realtime',{numberOfInputs:1,numberOfOutputs:1,outputChannelCount:[2]});const u=new URL(API_BASE_URL);const wsProto=u.protocol==='https:'?'wss://':'ws://';const tok=localStorage.getItem('sonic_token')||'';const wsUrl=`${wsProto}${u.host}${st.ws_url}${tok?'?token='+encodeURIComponent(tok):''}`;const ws=new WebSocket(wsUrl);fxRt.ws=ws;ws.binaryType='arraybuffer';ws.onopen=()=>{if(token!==fxRt.startToken){try{ws.close();}catch(e){}fxRt.starting=false;return;}fxRt.active=true;fxRt.starting=false;fxRt.inQueue=[];// bỏ audio stale sản xuất trước khi WS open (~4s load VST) — hết lag khởi đầu
+console.warn('[FX RT] start cancelled mid-flight — session stopped');try{window.SonicAPI.fxRealtimeStop({session_id:st.session_id}).catch(()=>{});}catch(e2){}fxRt.starting=false;return;}fxRt.sessionId=st.session_id;fxRtGuiPushShm();try{await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608242000`);if(token!==fxRt.startToken){fxRt.starting=false;return;}fxRt.node=new AudioWorkletNode(ctx,'sf-fx-realtime',{numberOfInputs:1,numberOfOutputs:1,outputChannelCount:[2]});const u=new URL(API_BASE_URL);const wsProto=u.protocol==='https:'?'wss://':'ws://';const tok=localStorage.getItem('sonic_token')||'';const wsUrl=`${wsProto}${u.host}${st.ws_url}${tok?'?token='+encodeURIComponent(tok):''}`;const ws=new WebSocket(wsUrl);fxRt.ws=ws;ws.binaryType='arraybuffer';ws.onopen=()=>{if(token!==fxRt.startToken){try{ws.close();}catch(e){}fxRt.starting=false;return;}fxRt.active=true;fxRt.starting=false;fxRt.inQueue=[];// bỏ audio stale sản xuất trước khi WS open (~4s load VST) — hết lag khởi đầu
 try{fxRtPushAllParams();}catch(e){}};ws.onmessage=ev=>{// Gap 8 (PDC realtime): text frame {cmd:'latency', total} tu server ->
 // cap nhat delay dry-bypass path (bu latency chain VST3 realtime).
 if(typeof ev.data==='string'){try{const d=JSON.parse(ev.data);if(d&&d.cmd==='latency'&&typeof d.total==='number'){fxRt.latencyTotal=d.total;// Chi delay dry path khi crossfade da xong (dry silent) — ap som
@@ -318,7 +318,7 @@ const fxRtSendFrames=d=>{if(!fxRt.ws||fxRt.ws.readyState!==1)return;try{const f=
 // chong race: neu stop/restart xay ra trong luc cho, bo qua.
 if(fxRt.fadedIn)return;setTimeout(()=>{if(token!==fxRt.startToken)return;fxRt.fadedIn=true;fxRtCrossfade(true,token);// Dry gan silent (tc 0.025) roi moi tre pdcDelay — tranh gap khi delay
 // dang lon dan.
-setTimeout(()=>fxRtApplyPdc(),250);},30);return;}if(d.type==='set_param'){try{fxRt.ws.send(JSON.stringify({cmd:'set_param',slot:d.slot,key:d.key,value:d.value}));}catch(e){}return;}if(d.type!=='in')return;fxRt.inQueue.push(d);fxRtInPump();};// Pace input: tối đa 1 block/kỳ (~5.8ms). Gửi dồn theo burst (main thread bị
+setTimeout(()=>fxRtApplyPdc(),250);},30);return;}if(d.type==='set_param'){try{fxRt.ws.send(JSON.stringify({cmd:'set_param',slot:d.slot,key:d.key,value:d.value}));}catch(e){}return;}if(d.type==='stats'){fxRt.stats=d;console.debug('[FX RT stats]',d);return;}if(d.type!=='in')return;fxRt.inQueue.push(d);fxRtInPump();};// Pace input: tối đa 1 block/kỳ (~5.8ms). Gửi dồn theo burst (main thread bị
 // rAF renderFrame block khi mở MASTERING PANEL) → SHM ring 4-slot tràn → mất
 // block → ngắt quãng.
 // Phase 4.2: fader SAU worklet — worklet chèn giữa outputAnalyser (chain
@@ -1699,7 +1699,7 @@ fxRtTrackReconcile(trackId,node,track);}catch(e){console.warn('rebuildTrackFxGra
 // Cần activeTrackNodesRef/isPlayingRef. Session giống master (fxRtStart):
 // fetch start → AudioWorkletNode 'sf-fx-realtime' → WS; WS open → splice
 // worklet vào chain hiện tại (đọc mods MỚI NHẤT — an toàn với rebuild).
-const fxRtTrackStart=async(trackId,track,path)=>{const key=trackId+':'+path;const chain=fxRtTrackChain(track);if(!chain.length)return;if(fxRtTracks[key]){if(!fxRtTracks[key].node||fxRtTracks[key].node.context!==getAudioContext())fxRtTrackStop(trackId,path,true);else return;}const ctx=getAudioContext();if(!ctx||!ctx.audioWorklet)return;const chainPayload=chain.map(s=>s.type==='vst3'?{type:'vst3',path:s.path,name:s.name||s.path,preset_b64:s.preset_b64||'',bypass:false}:{type:'builtin',id:s.type,params:s.params&&Object.keys(s.params).length?s.params:{},bypass:false});let st;try{st=await window.SonicAPI.fxRealtimeStart({fx_chain:chainPayload,sample_rate:ctx.sampleRate||44100});}catch(e){console.warn('[FX RT track] start fail',trackId,path,e);return;}const entry={sessionId:st.session_id,ws:null,node:null,ready:false,path,spliced:null,chainKey:fxRtTrackChainKey(chain),paramsBySlot:chain.map(s=>fxRtEntryParams(s,null)),inQueue:[],pumpTimer:null,lastInSent:0};fxRtTracks[key]=entry;fxRtGuiPushShm();try{await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608241900`);const node=new AudioWorkletNode(ctx,'sf-fx-realtime',{numberOfInputs:1,numberOfOutputs:1,outputChannelCount:[2]});entry.node=node;const u=new URL(API_BASE_URL);const wsProto=u.protocol==='https:'?'wss://':'ws://';const tok=localStorage.getItem('sonic_token')||'';const ws=new WebSocket(`${wsProto}${u.host}${st.ws_url}${tok?'?token='+encodeURIComponent(tok):''}`);entry.ws=ws;ws.binaryType='arraybuffer';ws.onopen=()=>{entry.ready=true;entry.inQueue=[];// bỏ audio stale trước khi WS open — hết lag khởi đầu
+const fxRtTrackStart=async(trackId,track,path)=>{const key=trackId+':'+path;const chain=fxRtTrackChain(track);if(!chain.length)return;if(fxRtTracks[key]){if(!fxRtTracks[key].node||fxRtTracks[key].node.context!==getAudioContext())fxRtTrackStop(trackId,path,true);else return;}const ctx=getAudioContext();if(!ctx||!ctx.audioWorklet)return;const chainPayload=chain.map(s=>s.type==='vst3'?{type:'vst3',path:s.path,name:s.name||s.path,preset_b64:s.preset_b64||'',bypass:false}:{type:'builtin',id:s.type,params:s.params&&Object.keys(s.params).length?s.params:{},bypass:false});let st;try{st=await window.SonicAPI.fxRealtimeStart({fx_chain:chainPayload,sample_rate:ctx.sampleRate||44100});}catch(e){console.warn('[FX RT track] start fail',trackId,path,e);return;}const entry={sessionId:st.session_id,ws:null,node:null,ready:false,path,spliced:null,chainKey:fxRtTrackChainKey(chain),paramsBySlot:chain.map(s=>fxRtEntryParams(s,null)),inQueue:[],pumpTimer:null,lastInSent:0};fxRtTracks[key]=entry;fxRtGuiPushShm();try{await ctx.audioWorklet.addModule(`${API_BASE_URL}/static/js/sf-fx-realtime.js?v=202608242000`);const node=new AudioWorkletNode(ctx,'sf-fx-realtime',{numberOfInputs:1,numberOfOutputs:1,outputChannelCount:[2]});entry.node=node;const u=new URL(API_BASE_URL);const wsProto=u.protocol==='https:'?'wss://':'ws://';const tok=localStorage.getItem('sonic_token')||'';const ws=new WebSocket(`${wsProto}${u.host}${st.ws_url}${tok?'?token='+encodeURIComponent(tok):''}`);entry.ws=ws;ws.binaryType='arraybuffer';ws.onopen=()=>{entry.ready=true;entry.inQueue=[];// bỏ audio stale trước khi WS open — hết lag khởi đầu
 fxRtTrackSplice(trackId,path);try{(entry.paramsBySlot||[]).forEach((pl,slot)=>pl.forEach(p=>ws.send(JSON.stringify({cmd:'set_param',slot,key:p.key,value:p.value}))));}catch(e){}};ws.onmessage=ev=>{if(!(ev.data instanceof ArrayBuffer)||!entry.node)return;const f=new Float32Array(ev.data);const half=f.length/2;const l=new Float32Array(half);const r=new Float32Array(half);for(let i=0;i<half;i++){l[i]=f[i*2];r[i]=f[i*2+1];}entry.node.port.postMessage({type:'out',l,r});};ws.onclose=()=>fxRtTrackStop(trackId,path,true);ws.onerror=()=>{try{ws.close();}catch(e){}};entry.node.port.onmessage=ev=>{const d=ev.data;if(!d||!entry.ws)return;if(d.type==='set_param'){try{entry.ws.send(JSON.stringify({cmd:'set_param',slot:d.slot,key:d.key,value:d.value}));}catch(e){}return;}if(d.type!=='in')return;// Burst 4 block (1024 mẫu) → tách 4 WS frame 512 floats → bridge batch 4.
 // Pace 1 burst/21ms (giống master) — tránh dồn frame sau stall làm tràn ring.
 entry.inQueue.push(d);const pump=()=>{if(!entry.inQueue.length)return;const now=Date.now();while(entry.inQueue.length&&now-entry.lastInSent>=FXRT_BURST_MS){entry.lastInSent=now;const dd=entry.inQueue.shift();if(entry.ws&&entry.ws.readyState===1){try{const f=new Float32Array(dd.data);if(f.length>512){for(let i=0;i<f.length;i+=512)entry.ws.send(f.slice(i,i+512).buffer);}else{entry.ws.send(dd.data);}}catch(e){}}}if(entry.inQueue.length){if(entry.pumpTimer)clearTimeout(entry.pumpTimer);entry.pumpTimer=setTimeout(pump,Math.max(1,FXRT_BURST_MS-(now-entry.lastInSent)));}else if(entry.pumpTimer){clearTimeout(entry.pumpTimer);entry.pumpTimer=null;}};pump();};}catch(e){console.warn('[FX RT track] setup fail',trackId,path,e);fxRtTrackStop(trackId,path,true);}};const fxRtTrackUnsplice=(trackId,path)=>{const entry=fxRtTracks[trackId+':'+path];if(!entry||!entry.spliced||!entry.node)return;try{entry.node.disconnect();try{entry.spliced.tail.connect(entry.spliced.dest);}catch(e){}entry.spliced=null;}catch(e){console.warn('[FX RT track] unsplice fail',trackId,path,e);}};// Chain đổi trên session ĐANG CHẠY — set_chain KHÔNG restart (bridge swap

app/static/js/sf-fx-realtime.js

@@ -30,8 +30,8 @@ class SfFxRealtimeProcessor extends AudioWorkletProcessor {
     super();
     this.BLOCK = 256;          // FXRT_BLOCK
     this.BURST = 4;            // số block gom 1 frame (bridge batch)
-    this.FILL = 24;             // 24 block ~128ms: buffer khởi đầu — hấp thụ jitter main-thread (GUI decode, rAF, solo restart)
-    this.CAP = 48;             // cap queue chặn overflow (~256ms)
+    this.FILL = 48;             // 48 block ~256ms: buffer khởi đầu — hấp thụ jitter main-thread (GUI decode, rAF, VST panel)
+    this.CAP = 64;             // cap queue chặn overflow (~341ms)
     this.HOLD = 2;             // 2 block ~11ms: lặp block cuối khi underrun (hết click) trước khi im lặng
     this.HOLD_FADE = 4;        // 4 block ~21ms: fade 1→0 sau HOLD hết (hết click cắt cứng)
     this.lastBlock = null;     // block cuối đã phát xong (hold khi underrun)
@@ -55,8 +55,14 @@ class SfFxRealtimeProcessor extends AudioWorkletProcessor {
       if (d && d.type === 'set_param') { this.port.postMessage(d); return; }
       if (!d || d.type !== 'out' || !d.l || !d.r) return;
       this.outQueue.push({ l: d.l, r: d.r });
-      while (this.outQueue.length > this.CAP) this.outQueue.shift();
+      while (this.outQueue.length > this.CAP) { this.outQueue.shift(); this.statCapDrop++; }
     };
+    // Telemetry (chẩn đoán crackle trên session thật): đếm sự kiện + báo main
+    // thread mỗi ~2s. Nếu user bật master FX nghe crackle mà stats cho thấy
+    // underruns>0 → delivery bị stall (main-thread busy) → nguồn crackle thật.
+    this.statUnderrun = 0; this.statHold = 0; this.statFade = 0;
+    this.statSilence = 0; this.statCapDrop = 0; this.statFadeIn = 0;
+    this.statCalls = 0;
   }
   process(inputs, outputs) {
     const input = inputs[0];
@@ -93,6 +99,14 @@ class SfFxRealtimeProcessor extends AudioWorkletProcessor {
     // block (không zero-fill → hết click/ngắt) rồi mới im lặng; resume NGAY
     // khi có block mới (không đợi re-buffer FILL) + không re-fade sau lần đầu.
     for (let i = 0; i < n; i++) {
+      this.statCalls++;
+      if (this.statCalls >= 1500) {  // ~2s @48k/128
+        this.statCalls = 0;
+        this.port.postMessage({ type: 'stats',
+          underruns: this.statUnderrun, holds: this.statHold, fades: this.statFade,
+          silences: this.statSilence, capDrops: this.statCapDrop, fadeIns: this.statFadeIn,
+          queueLen: this.outQueue.length });
+      }
       if (this.playing) {
         const blk = this.outQueue[0];
         if (blk) {
@@ -112,10 +126,12 @@ class SfFxRealtimeProcessor extends AudioWorkletProcessor {
         }
         // Underrun giữa stream — chuyển hold (không cắt zero ngay → hết click).
         this.playing = false;
+        this.statUnderrun++;
         if (!this.silenced) {  // đã im lặng (fade xong) → giữ im lặng, không hold lại block cũ
           this.holdPos = 0;
           this.holdLeft = this.HOLD * this.BLOCK;
           this.holdFadeLeft = this.HOLD_FADE * this.BLOCK;
+          this.statHold++;
         }
       }
       // Không phát: resume khi đủ block (lần đầu chờ FILL; sau đó chỉ cần 1
@@ -131,6 +147,7 @@ class SfFxRealtimeProcessor extends AudioWorkletProcessor {
           // fade-in nhanh tránh jump ~0→1 (click sau long stall).
           this.outGain = 0;
           this.fadeLeft = this.FADE;
+          this.statFadeIn++;
         }
         this.silenced = false;
         if (!this.hasStarted) {
@@ -159,7 +176,7 @@ class SfFxRealtimeProcessor extends AudioWorkletProcessor {
         this.holdPos++;
         if (this.holdPos >= this.BLOCK) this.holdPos = 0;
         this.holdFadeLeft--;
-        if (this.holdFadeLeft <= 0) this.silenced = true;  // fade xong → im lặng thật
+        if (this.holdFadeLeft <= 0) { this.silenced = true; this.statFade++; this.statSilence++; }  // fade xong → im lặng thật
         continue;
       }
       outL[i] = 0;