You are quite right that downstream power levels are too high (and one upstream channel is looking at the maximum allowable). This ought to be corrected simply because it is outside the spec. If you're not seeing much impact on speed, that's good, but I'd imagine from the large number of pre-RS errors that it is having some impact on latency (not to mention a few T3 timeouts showing in the log).
I would suggest waiting for the forum staff to pick this up, as it does need sorting out. If there's an area fault that might fix the issue, if there isn't then you'll need a technician visit.
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