fix: 流控状态未重置

update: 增加流式预缓冲

main/xiaozhi-server/core/handle/sendAudioHandle.py

@@ -94,37 +94,40 @@ async def sendAudio(conn, audios, frame_duration=60):
     send_delay = conn.config.get("tts_audio_send_delay", -1) / 1000.0
 
     if isinstance(audios, bytes):
-        if conn.client_abort:
-            return
-
-        conn.last_activity_time = time.time() * 1000
-
-        # 获取或初始化流控状态
-        if not hasattr(conn, "audio_flow_control"):
+        # 重置流控状态,第一次读取和会话发生转变时
+        if not hasattr(conn, "audio_flow_control") or conn.audio_flow_control.get("sentence_id") != conn.sentence_id:
             conn.audio_flow_control = {
                 "last_send_time": 0,
                 "packet_count": 0,
                 "start_time": time.perf_counter(),
                 "sequence": 0,  # 添加序列号
+                "sentence_id": conn.sentence_id,
             }
 
+        if conn.client_abort:
+            return
+
+        conn.last_activity_time = time.time() * 1000
+
+        # 预缓冲：前5个包直接发送，不做延迟
+        pre_buffer_count = 5
         flow_control = conn.audio_flow_control
         current_time = time.perf_counter()
-        
-        if send_delay > 0:
+
+        if flow_control["packet_count"] < pre_buffer_count:
+            # 预缓冲阶段，直接发送不延迟
+            pass
+        elif send_delay > 0:
             # 使用固定延迟
             await asyncio.sleep(send_delay)
         else:
-            # 计算预期发送时间
+            effective_packet = flow_control["packet_count"] - pre_buffer_count
             expected_time = flow_control["start_time"] + (
-                flow_control["packet_count"] * frame_duration / 1000
+                effective_packet * frame_duration / 1000
             )
             delay = expected_time - current_time
             if delay > 0:
                 await asyncio.sleep(delay)
-            else:
-                # 纠正误差
-                flow_control["start_time"] += abs(delay)
 
         if conn.conn_from_mqtt_gateway:
             # 计算时间戳和序列号
@@ -150,7 +153,7 @@ async def sendAudio(conn, audios, frame_duration=60):
         play_position = 0
 
         # 执行预缓冲
-        pre_buffer_frames = min(3, len(audios))
+        pre_buffer_frames = min(5, len(audios))
         for i in range(pre_buffer_frames):
             if conn.conn_from_mqtt_gateway:
                 # 计算时间戳和序列号