[Sephiroth]

The SH needs no time to settle down. There's only on way to measure your performance with any certainty and that's to have the SH in modem mode and either your own router or your PC wired to it. Then we can rule out the wretched thing which is known to be flakey in router mode especially if wireless is turned on.

Your downstream power levels are too high. If you has 8 channels (which you will in due course), those levels aggregated under the 3 dB doubling rule (you can look that up!) would exceed the 33 dBmv absolute input power level.

IMO your SH needs a 10 dB Forward Path Attenuator (VM engineer or eBay).

But there is something strange happening in that your upstream power is so high. If there was cable attenuation, the upstream would have trouble pushing through and would be high; but then the downstream would be low. But your upstream is high. If you ever see it at 55 dBmv or above, then things will slow down.

It could be high because it can't responde to keep-alives due to the high downstream power. So the first step is to put a 10 dB forward path attenuator on and see what happens.

And do please use modem mode if you don't want a whole can of whooppee what's wrong experience!