weak connection to internet with one device
I have a television connected in my basement bedroom with a wired ethernet connection to my router upstairs (Archer A7). I had to try this after wireless connectivity and mesh routers failed. I am using an Amazon Firestick 4k and I have 3 televisions upstairs that run perfectly with a wireless connection. My internet speed is 300mbps and I have tested the wired connection coming into the TV downstairs and I am showing that it actually exceeds that at the TV. However when I check the speed with the television running the firestick it shows the signal is too weak to run a program (around 6mg) and no programs will run.
I have switched out the Firesticks and changed the TVs. I just checked my Lan settings in the A7 router and chose IPv6, Dynamic IP, Connection Type = (SLAAC/DHCPv6), Lan=SLACC +STATELESS DHCP.
The television will run fine using a wireless iPhone as an access point. I am at my wits end with this problem. Please help?