HELP! Stereo dead

This evening after attending a meeting out of town I got in my Prius, turned it on, and the stereo was dead. I have a 2005 Prius with option package #6 which includes the upgraded 9 speaker JBL stereo, to which I added the PriusXM kit about half a year ago. I robooted the car several times, and the stereo did not come back. After driving for about 20 minutes I pulled over and rebooted the car a few more times and still no go. With the car on I hear a very faint high pitched tone coming from one of the right hand speakers as well as a noticable static pop about every two seconds. This noise is present whether I have the audio turned on or off. Adjusting the volume with the steering wheel controls or the knob on the head unit makes no difference. Switching between AM, FM, XM or CD makes no difference. The beeps that I normally get when switching between screens on the MFD is gone as well. However the talking dashboard lady in the NAV system, the bluetooth phone interface and the reverse beep still work. The popping sound every two seconds will likely drive me nuts during my commute.

Has anybody else experienced this or have any suggestions?

Currently very unhappy!!

- Bill