I know it's not your first rodeo...
I switched off bare wire and tinning my bare ends because of slippage in the binding posts.
That's just me.
If there is a loose connect I would expect intermittent cut-out. It would surprise me if you are experiencing multiple loose connects.
...Ha, as Shady chimes in!
What you are describing makes me think something is fritzing in the processor itself, unless it is happening in only one of the amps... but for multiple amps to be failing intermittently in the same way would be a little suspect.