The power levels are great, but the Signal to Noise Ratio (SNR) is marginal, and there are also uncorrectable errors. So it does look like a possible RF issue.
Also, you have 3 upstream channels, but only one at 5.1Msym/s, this is only half way to a good thing
(specifically, when everything is at the new standard, you should see two channels at 5.1 and one channel at 2.56. However, only getting 1 upstream channel is definitely BAD, so you've improved some..)
Have you applied a factory reset recently? If not:
»
192.168.100.1 --> Configuration and then click Restore All Defaults, confirm, and then click Reboot