Problem with LePou's LeCab?

[tsunamistar]

I have done proper gain staging making sure everything is below -12 db for headroom so there shouldnt digital distortion.

Im using the mac version of the lecab. But whenever I add a second mic to the cab I start getting some sort of "cracking" distortion kind of. like i cant raise the volume or it really starts cracking the sound.

I really need help Is it the samples or the amp sim?
using leGion

any help is welcomed!

 

[tsunamistar]

OH NVM it was my inteferace. had the tv plugged into he stereo out