So, I just installed my AC1200 Archer A6 V2.0 (this forum does not let me select my model for some reason), firmware is the latest, updated manually while connected via ethernet (ArcherA6v2_us_tw_c6us-up-ver1-1-7-P1[20201010-rel49458])

My networking setup is I have a modem with a single ethernet port, which connects to the router via ethernet, which then connects to 2 computers via ethernet.

So I mine cryptocurrency on my computer and for some reason, when I ping the server for my mining pool us1.ethermine.org, I am getting 10-15% packet loss. Latency only 9-11ms, but unacceptably high packet loss.

Before I hooked up the router, my modem was connected directly to one of my computers, while the other was connected to a nearby xfinity wifi hotspot. The connection directly to my modem produces zero packet loss, and my connection to the nearby xfinity wifi hotspot produces almost no packet loss.

With my computers connected to this router, either via ethernet cable or wireless, I am getting this massive packet loss when I ping my mining server. When I ping other servers, such as yahoo, google, gmail, zero packet loss. When I ping other mining servers, zero packet loss.

The strangest thing is that, when I turn on my vpn, I get zero packet loss from ethermine.org. When I turn the vpn off, the packet loss returns.

So I am at a loss. Based on the above, I know that the problem is not my ISP (because there's no packet loss when connected directly to my modem), and it's not the router's hardware being spotty (because I get no packet loss when connecting to other servers, and no packet loss to the server at issue when I connect through a VPN). I think that the answer must be simple, but I am just not knowledgeable enough about networking to figure it out.