diff --git a/src/call/call_audio.c b/src/call/call_audio.c
index ea15e62a..64a26b47 100644
--- a/src/call/call_audio.c
+++ b/src/call/call_audio.c
@@ -217,7 +217,11 @@ int call_audio_feed_pcm(uint64_t call_id, const int16_t* pcm, int count) {
     inst = g_inst;
     pthread_mutex_unlock(&g_mtx);
 
-    if (len <= 0 || !ua || !inst) return -1;
+    if (len <= 0) return -1;
+    if (!ua || !inst) {
+        DEBUG_ERROR(DEBUG_CATEGORY_CALL, "%s: feed_pcm: instance not set (call_audio_init not called)", CALL_AUDIO_ID);
+        return -1;
+    }
 
     struct call_media_arg* a = (struct call_media_arg*)u_malloc(sizeof(*a));
     if (!a) return -1;
diff --git a/tools/chatgui-android/jni_bridge/android_jni_bridge.c b/tools/chatgui-android/jni_bridge/android_jni_bridge.c
index 8457d0cd..fae1d9ba 100644
--- a/tools/chatgui-android/jni_bridge/android_jni_bridge.c
+++ b/tools/chatgui-android/jni_bridge/android_jni_bridge.c
@@ -1432,6 +1432,15 @@ int utun_bridge_call_is_online(const char* ch_id, uint64_t peer_node_id) {
  * ────────────────────────────────────────────────────────────────── */
 
 int utun_bridge_call_audio_start(uint64_t call_id) {
+    struct UTUN_INSTANCE* inst = instance_lite_get_instance();
+    if (!inst) {
+        DEBUG_ERROR(DEBUG_CATEGORY_CALL, "call_audio_start: no instance");
+        return -1;
+    }
+    if (call_audio_init(inst) != 0) {
+        DEBUG_ERROR(DEBUG_CATEGORY_CALL, "call_audio_start: call_audio_init failed");
+        return -1;
+    }
     return call_audio_start(call_id);
 }