Those downstream SNRs aren't too good. 32 is about the bare minimum for an acceptable signal on D2; with D3 I imagine the effects are even worse. How many splitters is your modem going through?
They're enough to hold sync but if your speeds appear to be suffering or you're getting packet loss, I'd place the blame on them. Ideally they should be at least 35 each. Are you getting your rated speeds?
Your upstream power is fine though. -- CableOne 50/2
I have yet to get up in the attic and check splitters. If not a direct line off the main splitter I will make it a dedicated run. Speed wise I was getting what I was supposed to till i just tested. 20.51\2.24. EEK!!!