Noise when using an instrument plugin

Dont know if this has been talked about already, but lately I'm gettin a lotta noise when I have an instrument plugin inserted in the REN software. At first, I thought this was only happening when I loaded TRILLIAN, but it seems to happen to every plugin right now.

It's some kind of a hiss with higher frequencies. I'll see If I can make an audio recording of it.

Have you tried increasing the audio buffer size?