Align Speechmatics STT TTFB metrics with STT classes

src/pipecat/services/speechmatics/stt.py

@@ -8,7 +8,6 @@
 
 import asyncio
 import os
-import time
 from enum import Enum
 from typing import Any, AsyncGenerator
 
@@ -598,9 +597,6 @@ class SpeechmaticsSTTService(STTService):
         if segments:
             await self._send_frames(segments)
 
-        # Update metrics
-        await self._emit_metrics(message.get("metadata", {}).get("processing_time", 0.0))
-
     async def _handle_segment(self, message: dict[str, Any]) -> None:
         """Handle AddSegment events.
 
@@ -804,28 +800,6 @@ class SpeechmaticsSTTService(STTService):
             yield ErrorFrame(f"Speechmatics error: {e}")
             await self._disconnect()
 
-    async def _emit_metrics(self, processing_time: float) -> None:
-        """Create TTFB metrics.
-
-        The TTFB is the seconds between the person speaking and the STT
-        engine emitting the first partial. This is only calculated at the
-        start of an utterance.
-        """
-        # Skip if metrics not available
-        if not self._metrics or processing_time == 0.0:
-            return
-
-        # Calculate time as time.time() - ttfb (which is seconds)
-        start_time = time.time() - processing_time
-
-        # Update internal metrics
-        self._metrics._start_ttfb_time = start_time
-        self._metrics._start_processing_time = start_time
-
-        # Stop TTFB metrics
-        await self.stop_ttfb_metrics()
-        await self.stop_processing_metrics()
-
     # ============================================================================
     # HELPERS
     # ============================================================================