I recently got a 06 is250 with a NAV radio and non ML audio. I have been having an issue where a good 50% of the time upon starting the car, the audio will not turn on at all. The screen and all buttons work perfectly fine. I use a BT transmitter connected to aux for music. I have tried to turn the audio on and off with the volume **** and still no prevail. I notice that upon start up and upon turning the audio on and off (while connected to aux), I hear two small pops from the main sub behind the back seats. I have also noticed what sounds to be a very faint crackling coming from behind the volume **** (not 100% that is the source). I have read on several forums that the CD player as well as the amp are common to die but I'm not sure what direction to go in. During the 50% of the time that the audio works, all the door speakers work fine but I do sometimes (maybe 25% of the time) notice that I'm not getting as much bass as normal. Could it just be the subwoofer causing a short in the system? Any input would be very much appreciated.

 

The popping is from the amp but the nav not working is probably the CD player. I replaced by amp on my 2007 2g is250 and the popping went away.

 

Check the area underneath and around the factory amp location (in trunk) for moisture. This is the cause for MOST factory amp issues, due to a poor design from the factory regarding the "pressure vent flap" near the amp location. Over time the flap just falls off or degrades and allows moisture into the amp area.

Funny story, I just purchased two factory replacement vent flaps last night from eBay. I don't want to have the same issue.