Official Mumble VoIP Forums

High CPU usage (≈40%) with workaround

It crashed, it is bugged, ...
Mumble (1.3.0~2424-1645 and 1.2.19?) is using approximately 40% of my CPU, but i was able to fix this problem by suspending a thread of the program with processexplore (the program works perfectly fine with the suspended thread).

This same problem happens to a different computer with different version of windows with the same workaround fixing the problem.

Is this a known bug or is it just me?
https://www.youtube.com/watch?v=KffIyoN ... e=youtu.be
Unfortunately those thread names aren't much help, are they? I'm pretty sure ucrtbase.dll is part of Microsoft's Universal C Runtime. I also can't reproduce this, though maybe someone else can.

After you suspend the thread, can you check and see if things like the Overlay, hotkeys (it sounds like you tested push-to-talk, but I think you did it inside of Mumble? Try it out of Mumble as well) and such all still work? If you disable the overlay does the CPU usage go away? What about positional audio?

I don't think it's anything directly audio-related, if you're able to still transmit (I take it you've verified you are actually transmitting audio? I *think* if you're sending out audio packets the icon lights up, but I'm not sure how that works on the local transmit side... I'm pretty sure all the audio related stuff is in a single thread though). We did have people complaining years ago about Mumble never really "idling", because we keep the AGC measurements going even when the user is not transmitting, not connected to a server, and so on, but I don't think that's related to this issue.

Thanks for looking into this.
It only happens when I launch the program with no internet connection. The high CPU usage goes away when I reconnect to the internet.
mike wrote:It only happens when I launch the program with no internet connection. The high CPU usage goes away when I reconnect to the internet.
Pretty much the same here. It slows my pc down to no end.