diff --git a/voice.py b/voice.py
index 2af58c6..85c01b3 100644
--- a/voice.py
+++ b/voice.py
@@ -791,16 +791,17 @@ class VoiceSession:
             if remote_identity:
                 logger.info("Linking to remote participant: %s", remote_identity)
 
-            # Publish activity video track (animated waveform bars)
-            try:
-                self._activity_video = ActivityVideoPublisher()
-                video_track = rtc.LocalVideoTrack.create_video_track("activity", self._activity_video.source)
-                pub_opts = rtc.TrackPublishOptions(source=rtc.TrackSource.SOURCE_CAMERA)
-                await self.lk_room.local_participant.publish_track(video_track, pub_opts)
-                self._activity_task = asyncio.create_task(self._activity_video.run())
-                logger.info("Activity video track published")
-            except Exception as e:
-                logger.warning("Failed to publish activity video: %s", e)
+            # Activity video disabled (MAT-149) — was causing lag
+            # TODO: re-enable when performance is investigated
+            # try:
+            #     self._activity_video = ActivityVideoPublisher()
+            #     video_track = rtc.LocalVideoTrack.create_video_track("activity", self._activity_video.source)
+            #     pub_opts = rtc.TrackPublishOptions(source=rtc.TrackSource.SOURCE_CAMERA)
+            #     await self.lk_room.local_participant.publish_track(video_track, pub_opts)
+            #     self._activity_task = asyncio.create_task(self._activity_video.run())
+            #     logger.info("Activity video track published")
+            # except Exception as e:
+            #     logger.warning("Failed to publish activity video: %s", e)
 
             # Load memories and user preferences for this caller
             memory_section = ""