Audio glitching before even streaming or recording

[MikeFloutier]

Hi, just setting up a new recording project. It's pretty simple:

1. Video source: iPhone via EpocCam - working fine
2. Audio source: Condenser mic > mixing desk > Interface > OBS - working fine
3. Audio source: Music keyboard > interface > Reaper/ReaStream standalone (DAW) > OBS - occasional glitches

I've reviewed the audio at the Reaper stage and it's completely clean - 44.1kHz 512 samples.

The OBS audio meter is NOT showing the remotest sign of clipping BUT I'm getting occasional glitches. I first noticed this in the OBS recordings BUT subsequently saw that they also occurred in the Monitored output (of just that channel) from OBS, even when NOT recording.

The log file shows that ever increasing buffering is being added until it reaches "Max Buffering" and appears to take some form of action before starting buffering again, and so on...

I'm guessing my glitches are what happens when Max Buffering is reached.

Not sure what's going on and how to sort it out.

Can you help please?

Kind regards,

Mike

https://obsproject.com/logs/RqYyj_4I_foSOZ26

 

[MikeFloutier]

Ok, well I tried a suggestion on another thread to disable all my other sources and begin adding them back until I found the culprit. Unfortunately (or not, depending on how you look at it) even with all other sources disabled the problem remained.

Next I tried disabling the EpocCam mic in Control Panel > Sound > Recording. That didn't make a difference.

Finally, in the Source's Properties I tried selecting the only other Device offered, which was my Interface.

Not sure why that worked but it seems to have done the trick.

 

[MikeFloutier]

Ok, well the truth is that my "solution" turned out to be a workaround but, as a workaround, it didn't really pass muster.

The problem being that, by using this workaround, I ended up having BOTH my audio Sources using the same Device. This, of course, defeats my aim to keep them on separate tracks; I simply end up with BOTH Sources on BOTH tracks....grr!

Ok, so here are my two audio pathways:

1. Condenser mic > Yamaha mixing desk > AudioBox interface > OBS, and
2. Midi keyboard > AudioBox interface > Reaper (DAW) > OBS (via ReaStream standalone; a Reaper plugin)

To recap, the condenser mic is fine using Pathway 1. Using Pathway 2 for my keyboard results in clicking/glitches occasionally; also I'm getting around 200ms latency. If I use Pathway 1 for the keyboard all is good (ie. glitches and latency disappear) BUT, as mentioned, this defeats my object of separate tracks.

Since AudioBox interface is simply passing Midi info to Reaper we can rule it out. Reaper is set to 512 samples and is giving latency of 15/12ms BUT when outputting via ReaStream (a Reaper vst plugin) to OBS (digital audio device & Reastream) this 200ms latency and glitches/clicking is introduced.

Just to give an idea of what I'm hearing, if I go into Reaper and steadily reduce my buffer block size from 512, around 128 I start to get the same clicking/glitching.

Any ideas?

 

[MikeFloutier]

Ok, well I seem to be getting somewhere.

Firstly I got ASIO4ALL installed which automatically got me a new category of Audio Input Capture sources.

Edit: then I downloaded https://github.com/Andersama/obs-asio/blob/master/images/TECH_ASIOsmall.png - the posthumously published OBS-Asio software.

This enabled me to route my DAW (Reaper) output (the problem output btw) via a Reaper plugin called ReaMote AND ASIO4ALL to OBS.

This has got rid of my latency AND glitching!!

My problem now, and this is entirely incidental, is that, having solved this, my desire to record my 2 audio sources to separate tracks, for subsequent mixing, is thwarted by the fact that NOTHING will record to Track 2. In spite of being enabled in Settings > Output > Recording > Audio tracks - Grrr

 

[RSSCommentary]

I just dumped thousands into a new OBS muti-cam green screen rig and I get everything set up and I'm having audio glitching issues. I tried setting everything to 44.1KHz but no good. The solution I came across was to unplug all the USB devices and get one working then re-add the rest of the USB devices one by one, ensuring all are set to 44.1KHz with no glitches, and it's working.

 

[RSSCommentary]

My Behringer USB audio interface output glitches but not my internal (Realtek) sound card. The 48KHz inputs work fine, it's the output causing the glitches. I personally am hitting the upper end of my 6-core i5-11400 with seven 4K cameras and 3 1080p cameras with multiple desktop and window captures. Some of the audio glitching was from the CPU overloading. The CPU overhead is 39% in OBS so it's the single-thread is the bottleneck, which is surprising because the i5-11400 single thread Geekbench is 1600.

One overlooked upgrade that can fix this issue is to ensure your RAM is matched with two sticks of fastest RAM your CPU can take, not one stick because we're copying so many huge buffers each frame the RAM may be a bottleneck. I've found that OBS Move Transition works well for reducing CPU overhead by hiding and showing windows at the start or end of movements.

You really need a CPU with 1800+ Geekbench single thread scores and 10000+ multi-thread score for this many cameras. The CPU is copying a lot of data, a better GPU won't help, so this is a perfect justification for overclocking.