So you hadn't REALLY read all the previous threads?
I suspect you are going to find your clipping noises are connected to either your shiny new focusrite audio device drivers misbehaving or the way you have reapers ASIO buffer set.
Quick and dirty method as always would be to run Resplendence.com's latency monitor and see what it throws up, but it sound s like you got caught by recent changes by both MS (AVAST, AVG,etc) and Focusrite "improving" their drivers at the same time.
I never could get a gen 1 saffire6, Scarlett2i2 or 2i4 to run with decent latency and no rice crispies once I upgraded from a dual core processor to an i5 some years ago. Hopefully the new drivers will settl down and gen 1 owners will finally get reliable performance again.