Good point.....im in NJ and this happend if the summer..winter..whenever!

I really cant find any correlation at all

However...I did use the stock radio wiring harness ground..which always works fine (at first) but the whine creeps back

i have a hunch that there is something amis within the Rio itself for I have a Sony player going into the AUX in on the Rio..and when i hook just the sony up i have absolutely no problem...ever..

what internal wiring in the rio might cause this?

i did have dome dry solder joints where the IDE cable hooks up to the motherboard and repared them.....perhaps a less than perfect soldering job would cause this (but then..why would it go away when i re-run the grounds?)