diff --git a/src/audio/google/google_rtc_audio_processing.c b/src/audio/google/google_rtc_audio_processing.c
index e3a8d95a72c9..c06f13eb4471 100644
--- a/src/audio/google/google_rtc_audio_processing.c
+++ b/src/audio/google/google_rtc_audio_processing.c
@@ -91,6 +91,8 @@ struct google_rtc_audio_processing_comp_data {
 	int aec_reference_source;
 	int raw_microphone_source;
 	struct comp_buffer *ref_comp_buffer;
+	int ref_frame_bytes;
+	int out_frame_bytes;
 };
 
 #if CONFIG_GOOGLE_RTC_AUDIO_PROCESSING_MIC_BITS == 16
@@ -607,7 +609,9 @@ static int google_rtc_audio_processing_prepare(struct processing_module *mod,
 	if (mic_fmt != bits_fmt(CONFIG_GOOGLE_RTC_AUDIO_PROCESSING_MIC_BITS)) {
 		comp_err(dev, "Mic stream must be %d bit samples\n",
 			 CONFIG_GOOGLE_RTC_AUDIO_PROCESSING_MIC_BITS);
-		ret = -EINVAL;
+
+		// FIXME: squash for now, the streams lie.  See below.
+		//ret = -EINVAL;
 	}
 
 	if (mic_fmt != out_fmt) {
@@ -615,6 +619,14 @@ static int google_rtc_audio_processing_prepare(struct processing_module *mod,
 		ret = -EINVAL;
 	}
 
+	// FIXME: the streams have a bad format on MTL, so we can't
+	// use this API.  Compute by hand.
+	//
+	//cd->ref_frame_bytes = source_get_frame_bytes(sources[cd->aec_reference_source]);
+	//cd->out_frame_bytes = sink_get_frame_bytes(sinks[0]);
+	cd->ref_frame_bytes = sizeof(mic_sample_t) * source_get_channels(sources[cd->aec_reference_source]);
+	cd->out_frame_bytes = cd->ref_frame_bytes;
+
 	/* Blobs sent during COMP_STATE_READY is assigned to blob_handler->data
 	 * directly, so comp_is_new_data_blob_available always returns false.
 	 */
@@ -777,7 +789,7 @@ static int mod_process(struct processing_module *mod, struct sof_source **source
 	 * samples so AEC compares the most recent values.
 	 */
 	if (ref_ok && fref > fmic)
-		source_release_data(ref, (fref - fmic) * source_get_frame_bytes(ref));
+		source_release_data(ref, (fref - fmic) * cd->ref_frame_bytes);
 
 	for (frames_rem = frames; frames_rem; frames_rem -= n) {
 		n = MIN(frames_rem, cd->num_frames - cd->buffered_frames);
@@ -814,7 +826,7 @@ static bool mod_is_ready_to_process(struct processing_module *mod,
 	 * Currently the topology sets IBS incorrectly
 	 */
 	if (ref_ok && (source_get_data_available(ref)
-		       < cd->num_frames * source_get_frame_bytes(ref)))
+		       < cd->num_frames * cd->ref_frame_bytes))
 		return false;
 
 	if (source_get_data_available(mic) < source_get_min_available(mic))
@@ -823,7 +835,7 @@ static bool mod_is_ready_to_process(struct processing_module *mod,
 	/* Output comes out all at once, the output sink much have
 	 * space for the full block
 	 */
-	if (sink_get_free_size(out) < cd->num_frames * sink_get_frame_bytes(out))
+	if (sink_get_free_size(out) < cd->num_frames * cd->out_frame_bytes)
 		return false;
 
 	return true;