How to tell if my 5ghz channel has gone bad?

Hi there.

I have a RT-AC87U router with the latest Merlin firmware on it.

I was wondering if there are any tests I can perform to test my 5ghz channel?

I've been noticing poor 5ghz performance lately.

Question... is the 5ghz led supposed to flash on and off? My 2.4ghz led light flashes/flickers consistently, which seems to be normal, but the 5ghz led light flashes on and off. Just an observation.

Any suggestions would be appreciated.

Cheers!