Need Help with HK radio and XM install

[DaCrema]

A good friend lives in Allentown. I am posting the question here because he is a member of Philly MINIs. I will also post the questions in the radio forum (http://www.northamericanmotoring.com...76#post1791576). He has a 06 MC and had a XM radio installed after picking up the car. All was good. Some few months ago his car was broken into and the XM radio was taken (thief likely thought it was a GPS unit). He has replaced the XM unit with a new Roady XT (same unit as before the theft). He was told by the installer that a FM modulator would be required now. The current radio has a high pitch hum when tuned to XM. To tune into regular radio one must open the trim part under the steering wheel and turn off the modulator with a small toggle switch. With the switch off, there is no hum in the radio. There is no hum in the CD with switch in either position.

Questions:
1. Does the HK unit allow install of the Aux input?
2. Does the HK unit allow install of XM Direct receiver in the boot (see http://www.northamericanmotoring.com/forums/showthread.php?t=31985&page=35&highlight=Harmon+Ka rdon+Radio )?
3. Can anyone here suggest a place to have the system looked at (in or near to Allentown)?

Thanks in advance