I'm trying to track down why I'm getting a ringing sound on my left channel. It sounds like tinnitus in your ear for those familiar with that, it will do it with no volume on the head unit and the ringing does not increase when the volume is increased. So, I don't have a problem drowning it out with music. It's more of an irritant and I'm not sure why it just started happening. The setup has been together since 2019 on my 2017 FLHX and I have had zero issues up until now.

It's a Sony XAV 5000 head unit with a Stinger SPX 700 amp powering Ground Zero yellow baskets in the fairing. I believe it's a Metra plug and play harness. I have the amp bridged and pushing a conservative 125 watts per side.

Things I've checked - both ground and power are routed directly to the battery. The wires are well-insulated and braided and securely attached at both ends, they are 8 gauge. I've replaced the RCA connectors with the same brand which I believe are decent, FosPower Y adaptors. All the wiring to the speakers are soldered and securely shrink-tubed.

I'm not sure what I'm missing or what to look at next. I'm wondering if it's maybe worn outputs on the amp or an issue with the harness. Any thoughts would be appreciated.

 

Swap the speaker wires. If the noise stays on the same side it's a speaker problem. If it goes to the other side it's a amp, radio, ground or wiring problem.

 

Finally, got a chance to mess with this. I flipped the speaker wires and the ringing went to the other side. Im confident with the ground and power wires. What do I look at next?

 

My guess is it's a problem with the amp or the head unit. If you bypass the amp and the sound goes away it's the amp. If you bypass and you still have the sound it's the head unit. You've ruled out the speakers by swapping the wires already. I would also check wiring on channel one or two, whichever one is giving you the whine. Maybe it's too close to an electronic part like a fan....

 

I bypassed the amp and the ringing went away. All of the amp inputs and outputs are good so it appears the amp is the culprit. Ordered another one from Amazon and hopefully that will be the end of it.
Thanks for the tips!