Hey folks. I recently bought a cheap ebay car charger for my N900, and i noticed that whenever i attempt to listen to music through my car stereo, the signal is great until i plug in the charger. The signal almost completely dies away and the noise gets worse - or seems to.


At first i thought it was the car charger, as that was the first time i noticed. But today i tried it with my home stereo and the Nokia AC charger (australian edition) and the same thing happened. In fact, the problem remained after i unplugged it. Which was a bit worrying. But i uninstalled fm rds notify and rebooted, and it came good again - and now once again the signal dies away when the charger is plugged in but returns to normal when it's removed.

I don't know if fm-rds-notify is responsible for the problem latching like that for sure, though. Also: When the charger isn't plugged in to the wall nothing happens.


I'm running the power kernel at the moment, though it happened on the nokia kernel too if i remember. Everything else on the phone works fine (built in speakers, headphone output, other hardware like gps, etc) as far as i can tell at least.

Has anyone had this problem? It's almost like the radio output power is being set to minimum when charging, which is backwards!

Anyway thanks.

I have the same problem, but I don't use the FM transmitter on a daily basis so haven't been too concerned by it.

When you charge the phone with the standard FMTX you will get a major signal power drop. This is something Nokia implemented(maybe for overloading the FMTX Chip?)

But the solution is:

1. Use FMBoost from the repositories or
2. Use the modified FMTXD file from this post http://talk.maemo.org/showthread.php?t=60567

I prefer the usage of the modified FMTXD File because it will stay at an constant powerlevel. when you use FMBoost you will need to activate it everytime you put a charger in the N900.

I was wondering about the fm boost thing. Thanks for that! With pr1.3 my phone's battery seems to last ages, so losing extra power on the drive to work won't be a big deal.

Thanks again!