Buffer underruns

[jnastic]

Hi everyone.
I've been using Reaper for a long time now and it was pretty stable for live/recording use.
Typically, I'd record/monitor :
- 1 guitar + Helix Native
- 1 guitar
- 1 bass + Cerberus Bass Amp
- 3 microphones + lightweight FX
- 1 e-drum + Addictive Drums

Recently, I've upgraded my setup with 3 old iPads (with TouchOSC) and ReaLearn to give my musicians some hands-on control.

But I've got a lot of underruns, especially when recording (with a RME Babyface Pro, 256 samples, on a MacBook Pro).

I've noticed that the underruns go away (or are less frequent) when the FX windows are closed.

So, the point of this post is to have a few tips on optimizing my setup to avoid these buffer problems in the future.

Any tip is welcomed!

Are the controle surfaces taking to much CPU?
Are the FX GUIs taxing the CPU?
I'm really trying to figure out the culprit.

Thanks!

[mschnell]

Control surfaces and GUI are handled in an OS thread that has lower priority than the Audio threads. So that will not produce any buffer underrun.

Very likely the "culprit" is one or multiple plugins.

-Michael

[jnastic]

Thanks for the answer.

I've had 2 more intense jam sessions with the same setup, but I've changed the Thread Behavior and #CPUs for Live FX and everything is doing just fine.

I think my settings weren't optimal for Live usage.

I'll have to do more testing eventually.