强切换行哑火根治(实机病灶):封行动作被三处早退吞掉——①强切时无进行中句(owner=-1),强制endpoint落进无句分支只有resetBuffer,永无finalize;②finalizeSentence两个早退(sentenceById缺失/重复定格)在封行代码之前。修:封行移至finalizeSentence入口(早退前);无句分支补发closeOnsetLineIfPending;预置标签加5s保鲜期防误挂;修复后链路:强切→封行→新句新行挂S1,日志ONSET-CLOSE/ONSET-LINE可查

app/src/main/java/com/k2fsa/sherpa/onnx/MainActivity.kt

@@ -221,6 +221,7 @@ class MainActivity : AppCompatActivity() {
     private val onsetMinSamples = 19200     // 1.2s 开口窗
     @Volatile private var onsetSeq = 0L     // 行切换/会话开始作废在途开口判定
     private var pendingOnsetLabel: String? = null // 主线程:下一新行预置标签
+    private var pendingOnsetLabelAt = 0L          // 预置标签时间戳(过期作废)
     private var onsetClosePending = false         // 主线程:强切后旧句定格即封底行
     @Volatile private var rollingLowHits = 0
     // 无缝插话确证(2026-09-15):SUSPECT 等停顿会被"对方话没停就接话"憋死
@@ -851,9 +852,11 @@ class MainActivity : AppCompatActivity() {
                                 rmsOf(samples) else 0f) + ")")
                     switchSuspicionAtMs = 0L
                 }
+                var forcedEp = false
                 if (fastEp) {
                     val forced = pendingForceEndpoint
                     pendingForceEndpoint = false
+                    forcedEp = forced
                     rollingLowStreak = 0
                     switchSuspicionAtMs = 0L
                     silenceRun = 0
@@ -905,7 +908,13 @@ class MainActivity : AppCompatActivity() {
                             finalizeSentence(sid, accepted)
                         }
                     } else {
+                        // 强切但无句可定格(owner=-1):封行/预置标签仍在
+                        // 主线程挂着,finalizeSentence 永不来的这条路径上
+                        // 补发封行,否则换行哑火(2026-09-16 现场根因)
                         resetBuffer()
+                        if (forcedEp) {
+                            uiHandler.post { closeOnsetLineIfPending() }
+                        }
                     }
                 }
             }
@@ -1618,6 +1627,7 @@ class MainActivity : AppCompatActivity() {
         val list = if (historyMode) stashedLiveLines ?: subtitleLines else subtitleLines
         val bottom = list.lastOrNull() ?: return
         pendingOnsetLabel = label
+        pendingOnsetLabelAt = SystemClock.elapsedRealtime()
         if (!bottom.open) return   // 底行已封:下一行自然消费预置标签
         val busy = bottom.sentences.any { !it.finalized }
         if (busy) {
@@ -1628,6 +1638,14 @@ class MainActivity : AppCompatActivity() {
         }
     }
 
+    /** 强切落进"无句可定格"分支时的封行兜底(主线程);预置标签保留等待下一行 */
+    private fun closeOnsetLineIfPending() {
+        if (!onsetClosePending) return
+        onsetClosePending = false
+        subtitleLines.lastOrNull()?.takeIf { it.open }?.open = false
+        Log.i(TAG, "ONSET-CLOSE no-sentence forced endpoint")
+    }
+
     private fun appendNewLine(label: String?): SubtitleLine {
         // 新行出现即封掉之前的开放行,并把其中"未定格的进行中句子"整体迁移
         // 过来 —— 硬保证 in-progress 只可能发生在最底行(修复:声纹判定搬家后,
@@ -1642,12 +1660,23 @@ class MainActivity : AppCompatActivity() {
             old?.sentences?.removeAll(migrating.toSet())
         }
         // 开口即查预置标签(ONSET-SWITCH 判了新说话人)→ 新行直接采用,
-        // 并成为"最近确认说话人"(后续空闲新行沿用);不等 endpoint 权威判定
-        val eff = pendingOnsetLabel ?: label
-        if (pendingOnsetLabel != null) {
+        // 并成为"最近确认说话人"(后续空闲新行沿用);不等 endpoint 权威判定。
+        // 超 5s 未消费 = 强切未落地(如无句可定格且无后续新句),作废防误挂
+        val preset = pendingOnsetLabel
+        val eff: String?
+        if (preset != null &&
+            SystemClock.elapsedRealtime() - pendingOnsetLabelAt < 5_000L
+        ) {
             pendingOnsetLabel = null
-            lastConfirmedLabel = eff
-            Log.i(TAG, "ONSET-LINE new line label=$eff")
+            lastConfirmedLabel = preset
+            eff = preset
+            Log.i(TAG, "ONSET-LINE new line label=$preset")
+        } else {
+            if (preset != null) {
+                pendingOnsetLabel = null
+                Log.i(TAG, "ONSET-LINE stale preset dropped")
+            }
+            eff = label
         }
         val line = SubtitleLine(
             id = lineIdSeq.incrementAndGet(),
@@ -1700,6 +1729,13 @@ class MainActivity : AppCompatActivity() {
     // endpoint/强制断句的 settle:该句就地定格(归属修正走 confirmSpeaker,
     // v5 起声纹判定已移出录音线程)。
     private fun finalizeSentence(sid: Long, willRefine: Boolean) {
+        // 开口即查/强切封行:必须在任何早退之前执行——sentenceById 缺失或
+        // 重复定格都会从下面两行 return,尾部执行曾让封行永哑
+        // (2026-09-16 现场:强切 owner=sid-1,强制 endpoint 无句可定格,换行丢失)
+        if (onsetClosePending) {
+            onsetClosePending = false
+            subtitleLines.lastOrNull()?.takeIf { it.open }?.open = false
+        }
         lastSettledSid = sid
         lastSentenceSettledAt = SystemClock.elapsedRealtime()
         val sentence = sentenceById[sid] ?: return
@@ -1720,12 +1756,6 @@ class MainActivity : AppCompatActivity() {
             // (SKIP_SHORT 等情况 submitRefineTask 已写对账日志,不重复记)
             sentenceById.remove(sid)
         }
-        // 开口即查强切:旧句已定格,此刻封底行,让新说话人首句另起带
-        // 预置标签的新行(由后续 onPartial 尾部创建)
-        if (onsetClosePending) {
-            onsetClosePending = false
-            subtitleLines.lastOrNull()?.takeIf { it.open }?.open = false
-        }
         sentence.line?.let { notifyLine(it) }
         autoScroll()
     }