diff --git a/src/classic/btstack_cvsd_plc.c b/src/classic/btstack_cvsd_plc.c
index 46cf0fa6b..d768c6173 100644
--- a/src/classic/btstack_cvsd_plc.c
+++ b/src/classic/btstack_cvsd_plc.c
@@ -247,6 +247,7 @@ static int bad_frame(btstack_cvsd_plc_state_t *plc_state, BTSTACK_CVSD_PLC_SAMPL
 }
 
 void btstack_cvsd_plc_process_data(btstack_cvsd_plc_state_t * plc_state, BTSTACK_CVSD_PLC_SAMPLE_FORMAT * in, uint16_t size, BTSTACK_CVSD_PLC_SAMPLE_FORMAT * out){
+    if (size == 0) return;
     if (plc_state->cvsd_fs == 0){
         if (size > CVSD_FS_MAX){
             log_error("btstack_cvsd_plc_process_data: audio frame size is too large.");
diff --git a/test/hfp/pklg/test4.pklg b/test/hfp/pklg/test4.pklg
deleted file mode 100644
index 0037b2921..000000000
Binary files a/test/hfp/pklg/test4.pklg and /dev/null differ