OBS have to toggle monitor off then on at each startup


New Member
Hi guys,

Firstly my appreciation. My charity group just did a 30-hour non stop broadcast over the weekend and used OBS, we were amazed at the quality and output we could do using this fantastic software, really well done to all creators, contributors, etc. Thank you!

Version: 26.0.2 (64 bit) running on Windows 10 professional. No virtual sound devices, etc, just 1 built in sound card. AMD Radeon gfx card.

Now onto a little bug that we found, or that I have misconfigured. I created many scenes with different content, media source, video capture, etc, etc.
For the media source I used a combination of mkv, mp4 and others. Playback worked great, however the audio monitor seemed to do this.
The Media source was added and has ticks in "Local File, Restart playback when source becomes active, Use hardware decoding where available, Show nothing when playback ends, Close file when inactive.

At each program launch, although the Audio Monitor showed "Monitor and output" it did not send to monitor only output. I had to go into Advanced Audio, Audio Monitoring on the media source and toggle it to monitor off then back to Monitor and Output before we got audio out the monitor.

Audio output/monitor device was the normal PC soundcard/rear output port.

Am I missing something here in a setting or is this a potential bug I've found?
Thanks in advance!


New Member
Andy, we're dealing with right now too. Did you find a fix other than toggling the setting in the Advanced Audio Settings?

Bernd Uhlmann

New Member
OBS version 27.1.3 (64 bit, WIN 10 or older). Media Player using MP3 music file (and other audio-only formats).

Typically, you will load an MP3 file to OBS as a “Media Source” and enable monitoring to a windows default output device. I understand that this uses the “ffmpeg” media player.

If the MP3 song has NO cover image (MP3-Tag ID3 frame 'PIC' or 'APIC') everything works fine as intended.

Any MP3 song with a cover image causes a set of issues:

The song starts normally and continues until anything interrupts the normal flow such as:
  • If the scene is briefly changed. After returning to the scene with the song, the song will no longer be monitored.
  • If the end of the song reached. Even if the song is supposed to loop, while it loops, it will no longer be monitored.
  • If you interfere with the source via the media control, i.e. by stopping the song or using the media slider in any way, the song will no longer be monitored.
If monitoring the song ended unintentionally due to any of the above issues, it can be manually restarted via “Advanced Audio Setting”, stop monitor and start monitoring again.

Further side effect: monitoring a looping song containing a cover image will stop monitoring at the first loop but monitoring will restart by itself after a single unmonitored loop.

Another related Problem with MP3 media:

Any MP3 song with a cover image will cause the above problems with monitoring. If you later replace the song with another song (via Source properties – select another local file without an image), then the old image stays on the scene. The new and different song works fine but now the old image is stuck with the Source on the scene until you remove the source altogether.