Stereo issues.

Last couple of days I've had an issue with my Sony stereo. Friday the stereo was working just fine, until I went to the gym. When I got in the car and turn the stereo on, it just blared a loud steady tone and none of the controls on the cd face or remote worked, volume, menu, source nothing. The only way to stop the noise was to either turn the car off or remove the stereo face.

Went home and pressed the small reset button. Everything worked just fine like it had for the pass few years, over this past weekend and all day today. Monday evening I left the gym (same place), got in and turn the car on and was going demo my new Hertz for someone and it did the same thing. A very loud steady tone noise and on the cd player digital menu screen was the infinte symbol/sideways figure 8 and nothing worked.

Both times the stereo worked once I got into the parking lot but it was after an hour or two when I went to leave did the problem happen. Worked ok at work, the entire weekend (walmart, mall, ect...)

I got a few blocks away and reattached the player face and it played just fine without reset.

Could it be a stereo scrambler or something? No one else has any issues with their system.

Any ideas?

Check list: fuses, rca's, amp fuses, ground, ect All fine.