I have a Behringer XR18 with Two Audio Headsets Connected to it. I am able to receive their audio feed on vMix without any issues. However, when I send audio to the XR18, it pops and clicks. I am told that this is a buffer issue and I have tried to change the buffer size on the Behringer Drivers but it always defaults to 1024 once the vMix Audio Send is started.

Is there a solution to this? If not, what's another way to send an audio out to the mixer? Aux out of the PC?

one thing to try (if you're not already) would be to use only the XR18 device for all the inputs and outputs in vmix.. its potentially not a good idea to use one audio device for some outputs and another device for others.. for example using the XR18 for main output and busses and then using onboard audio for headphones because i dont think there is a master clock between the different devices..

It would actually be interesting to hear from Martin how vmix allows you to use different audio devices for different outputs ? ive always thought one master clock source was required for them to stay in sync..