diff --git a/voice.py b/voice.py
index b5b9ad0..a0b1076 100644
--- a/voice.py
+++ b/voice.py
@@ -257,6 +257,24 @@ class VoiceSession:
             logger.info("Connected (E2EE=HKDF), remote=%d",
                         len(self.lk_room.remote_participants))
 
+            # Element Call rotates its encryption key when bot joins the LiveKit room.
+            # We fetched the pre-join key above; now wait for EC to generate and publish
+            # the post-join rotated key via Matrix timeline.
+            pre_max_idx = max(self._caller_all_keys.keys()) if self._caller_all_keys else -1
+            logger.info("Polling for EC key rotation (pre-join max_idx=%d)...", pre_max_idx)
+            for _attempt in range(10):  # poll up to 5s (10 × 0.5s)
+                await asyncio.sleep(0.5)
+                await self._fetch_encryption_key_http()
+                new_max = max(self._caller_all_keys.keys()) if self._caller_all_keys else -1
+                if new_max > pre_max_idx:
+                    self._caller_key = self._caller_all_keys[new_max]
+                    logger.info("Key rotated: index %d→%d (%d bytes)",
+                                pre_max_idx, new_max, len(self._caller_key))
+                    break
+                logger.debug("Key rotation poll %d: max_idx still %d", _attempt + 1, new_max)
+            else:
+                logger.warning("No key rotation after 5s — using pre-join key[%d]", pre_max_idx)
+
             # Set per-participant keys via key provider
             kp = self.lk_room.e2ee_manager.key_provider
 
@@ -279,21 +297,24 @@ class VoiceSession:
                     if remote_identity:
                         break
 
-            # Set caller's per-participant key (HKDF info=caller_identity = matching EC JS).
-            if self._caller_key and remote_identity:
+            # Set ALL known caller keys (per-participant, HKDF info=remote_identity).
+            # EC may have already rotated (index 0→1) by the time bot connects.
+            if self._caller_all_keys and remote_identity:
                 try:
-                    kp.set_key(remote_identity, self._caller_key, 0)
-                    logger.info("Set caller key for %s (index=0, %d bytes)", remote_identity, len(self._caller_key))
-                    # Also set via caller_identity (belt+suspenders if identities differ)
+                    for idx, k in sorted(self._caller_all_keys.items()):
+                        kp.set_key(remote_identity, k, idx)
+                        logger.info("Set caller key[%d] for %s (%d bytes)", idx, remote_identity, len(k))
+                    # Belt+suspenders: also set via matrix identity if different from LK identity
                     if self._caller_identity and self._caller_identity != remote_identity:
-                        kp.set_key(self._caller_identity, self._caller_key, 0)
-                        logger.info("Also set caller key via identity %s", self._caller_identity)
+                        for idx, k in sorted(self._caller_all_keys.items()):
+                            kp.set_key(self._caller_identity, k, idx)
+                        logger.info("Also set all caller keys via identity %s", self._caller_identity)
                 except Exception as e:
-                    logger.warning("Failed to set caller per-participant key: %s", e)
-            elif not self._caller_key:
-                logger.warning("No caller E2EE key — incoming audio will be silence")
+                    logger.warning("Failed to set caller per-participant keys: %s", e)
+            elif not self._caller_all_keys:
+                logger.warning("No caller E2EE keys — incoming audio will be silence")
             elif not remote_identity:
-                logger.warning("No remote participant found — caller key not set")
+                logger.warning("No remote participant found — caller keys not set")
 
             if remote_identity:
                 logger.info("Linking to remote participant: %s", remote_identity)