Did that "noise" sound like sample rate reduction or ring modulated?
The latest OS is 1.1.5.1 an that one fixed some bugs concerning something that sounded like rate reduction og ring modulation... it's not completely fixed though, and it is still on their Bug Fix list for a future update.
It sounds to me like this is the bug you experienced... it happens with certain modulation settings in the Mod Matrix, and usually only on layer B... when it is first heard, it's impossible to get rid of it, and it sounds on all other patches until you switch off the REV2 and turn it on again.