DHCPv6[31364]: 72001011-DHCPv6 - Missing Required Option 82 and 24 (Internet intermittent drops/lag spikes/etc.)

@EG is better at signal analysis, but your downstream power is drifting too high at that particular moment.  A bummer you can't see correctable/uncorrectable errors on that one.  If you could, that would likely be your connection stumbles.  When you notice a problem, check it again.  They may be drifting higher too and can vary over time.

Is that thing rebooting on you too?  High power signals can cause reboots.  It's a bit cryptic, but when the link is retraining, before you are really online, dhcp6 attempts to contact upstream throw those 82/24 errors because there was no response.  They happen in my area frequently and normally on a dhcp6 renew after an address release.  Flooded/DoS attacked upstream DHCP6 server?  Dunno.  They don't want to seem to troubleshoot it, and the renew is unreliable.   My work around was to disable DHCP6 entirely for my firewall/lan traffic, and that works.  Not an optimal situation, but for what I do it's a workable thing.

When one of my drunken neighbors ran over the cable box on the street here, my signal power doubled overnight after they "fixed the cable".  I ended up tossing in an $8 attenuator to knock the signal down, and that works.  Fixed their cable install too.  No ground block, broke open the cable box on the house and found it was just the cable out of the ground, to an F-81 connector to another cable that ran to my modem.  Nothing in the box.  No PoE filter either but I don't care. No MoCA on my stuff.  That was NOT the cause of the increased signal levels and had no impact on performance/quality, although I might get a bit luckier on a close lightning strike not frying my modem.

You can call a tech out to take a look if you don't want to mess with it.  If it's upstream, you won't be charged.  If there is a wiring problem, splitters in your house, you could be.  I had no faith after seeing their install so I fixed it myself and it was a good time to shorten and use better cables/connectors.

@Dream32 

This may or may not be the root cause of the problem (YMMV) but it should be addressed regardless.

As stated by others, the downstream power is on the high side and it may be over-driving the front-end receiver circuit of the modem. That can cause waveform distortions, random disconnects, spontaneous re-booting of the modem, speed, packet loss, latency problems, and the un-bonding of channels.

Is there a drop amplifier on the coax cable line leading to the modem ? If so, try removing / bypassing it and see. If not, you can try installing a -6 dB forward path-only attenuator pad such as this one in the link below on the coax port on the rear of the modem to knock that power level down and see;

https://www.amazon.com/FPA6-54-Forward-Attenuator-DOCSIS-Internet/dp/B08KTRC3XZ  

It won't affect the upstream power level which is within spec. Good luck !

Hope that was it and that things hold up for you ! Perhaps you should give it just a bit more time and see. Please post back here if the problem returns. Good luck !

The -6db attenuator fixed the problem previously, but it's come back recently and my power levels vary way more than before across the board.

I've tried removing the -6db but the problem got even worse.

Event Logs

These are my power levels with the -6db attenuator