I was driving to the gym today & playing around with the navi screens (lots of long red lights). I found a screen that plays all the voice commands via the female voice. I was trying to memorize a few but had to cancel. When I got back to the TL, I noticed a few things out of whack...
1) All radio & XM presets were gone (default) & XM was set to channel 1 on all spots (XM1 & XM2). Bass/treble, etc all reset)
2) uploaded phone book was gone.
3) climate control was reset.

I find it strange that my nav is fine. All saved destinations are in-tacked. Driver controls are untouched (seat, preferences). Battery is fine (2008).

Is this a one time thing or is there a known flaw I just experienced?

 

my girlfriends car did that (not a TL tho) but I couldnt find anything wrong other than a low battery.

The only thing I could think of was with the battery so low, when she started cranked over the engine, the power level dropped so much, that it cleared the presets...

After a new battery it never happened again

 

a low battery shouldnt be the case since his seats and other stuff didnt get cleared. It might be just one of those random flaws. Try repeating what you did before and see if that happens.

 

I know it is a long shot but if you used the 2nd set of keys to drive the car that day it could be the culprit. The presets are saved according to driver 1 or driver 2. I would think this would have effected the nav as well but maybe not.