flakey tuner issues

I've got an original, Rio-brand tuner module in my car. It's been running percently since I got it three years ago. In the last week, it's started misbehaving.

When the car is cold in the morning, it will work fine. After three or four minutes, after it's heated up, it starts flaking out. The signal meter will go from full to nothing and back to full once or twice per second. You hear sound drop-outs but no scratchiness or other noises that would indicate a flakey connector. After the car sat in the parking lot for most of the morning and afternoon, I got about a minute of music out of it until it started flaking out again.

Furthermore, even with the car off and parked, the drop-outs still continued. This tends to rule out any connector issues. Could it be a heat-reated issue, perhaps a solder joint gone bad? Anyone else experienced anything like this?

From what little I know about the tuner kit design, and presuming it applies to the original tuner too...

The audio signal and the FM signal strength signal get separated fairly soon from the tuner module. So if both are dropping out then the fault is fairly early in the chain. Think power supply or tuner module.

Heat is definitely suspected. It could be a solder joint going bad, or a component going bad.

If you aren't getting the "Hisssss" that comes from loss of signal, yet it loses audio, then it sounds like the dreaded faulty Op-amp problem that is (apparently) common (?) on the factory ones. It's a straightforward replacement.

Hmm. Which op-amp? Don't know. Patrick does, I hope he chimes in on this one.

Yup, no hiss at all, and another day of playing around seems to confirm my heat-related theory. Hmm....