Two electrical questions - OEM alarm horn and radio

[dictoresno]

One of the shorts my 86 911 had while my dad still owned it was every time the battery had power, the OEM alarm horn (the one mounted under the steering rack) would constantly blare. not honking, just a long constant alarm. When I got the car from him, I was able to reach under and unplug the horn to keep that from going off. Im sure there's a short, just don't know where. Over the winter layup, I want to tackle it. I have the wiring diagrams, but wanted to know if anyone else ever had that horn short and if it's a common easy fix. The short doesn't appear to drain the battery or anything.

Second question is I removed my father's 20+ year old nonworking Blaupunkt and installed a new one. It worked great, with no issues for months. Now, ive noticed every time I start the car, the radio has been reset to its defaults and I need to keep readjusting it. It's almost as if the constant power wire fell out. Im gonna remove the radio soon to peek back there. Anyone else ever had that happen? The car has a 1985 ADS Power Plate 100 amp under the passenger seat, but I doubt that's where it's getting its constant from.

Any advice would be appreciated.