said by andyross:As mentioned, your upstream levels are too high. With 3-channel (or more) bonding, the limit is 51dB for 64 and 32QAM, and 52dB for 16QAM. It's 54/55 for 2-channel, and 57/58 for single.
Well that explains why I'm dropping down to a single channel. I had massive packet loss this morning.
I'm back on one channel and my upstream power is now 55.2500 dBmV.
Ironically, my connection is working a lot better now with one one channel which I guess is based on the above.