diff --git a/CHANGELOG.md b/CHANGELOG.md
index bf2275b..0d643ee 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -5,6 +5,10 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [4.0.6] - 2025-06-19
+
+- Moved channel_diarization_labels field from realtime transcription config to common class.
+
 ## [4.0.5] - 2025-06-18
 
 - Added missing flag to call_middleware for multichannel mode.
diff --git a/VERSION b/VERSION
index 8b2dd6c..9eefef7 100644
--- a/VERSION
+++ b/VERSION
@@ -1 +1 @@
-4.0.5
\ No newline at end of file
+4.0.6
\ No newline at end of file
diff --git a/speechmatics/models.py b/speechmatics/models.py
index 764e656..c0539f0 100644
--- a/speechmatics/models.py
+++ b/speechmatics/models.py
@@ -134,6 +134,9 @@ def asdict(self) -> Dict[Any, Any]:
     transcript_filtering_config: Optional[dict] = None
     """Configuration for applying filtering to the transcription."""
 
+    channel_diarization_labels: Optional[List[str]] = None
+    """Add your own speaker or channel labels to the transcript"""
+
 
 @dataclass
 class RTSpeakerDiarizationConfig:
@@ -304,9 +307,6 @@ class TranscriptionConfig(_TranscriptionConfig):
     audio_events_config: Optional[AudioEventsConfig] = None
     """Optional configuration for audio events"""
 
-    channel_diarization_labels: List[str] = None
-    """Add your own speaker or channel labels to the transcript"""
-
     def as_config(self):
         dictionary = self.asdict()
         dictionary.pop("translation_config", None)