A few days ago my Mark 2 player began malfunctioning. Every time it restarts (whenever the car is turned off) the volume level resets to -46.

The rotary encoder was replaced a long time ago (>10 years) and has given no trouble since, seems to be working properly now.

How can I fix this problem?

tanstaafl.

If you have a hijack kernel installed, there is an option in the Hijack kernel for "Volume Level On Boot". That might have gotten accidentally pressed, and configured to "Use current volume", at a moment in time when your player volume was set to -46. To fix it, set it to "Use previous volume." Then the player will boot up at whatever volume level it was at when the power was last pulled.

Also note: the "Volume level on boot" setting is separate for home-mode/car-mode, so if the player is booting into the opposite mode that you expect it to, it might be another accidentally-selected hijack setting (force DC/Car mode or force AC/Home mode), or a bad DC jack on the player, with the sensing switch getting flaky on the jack. (Details here: http://riocar.org/FAQ/8/87.html#87 )

Can you try it in the home with a serial cable attached to grab the log messages?

I have no proof, but I am 90% sure that is exactly what happened. The stereo was working fine when I brought my car in to the dealer for servicing. The mechanic, not wanting to listen to Mozart (or anything else, for that matter) found the volume knob and turned the volume all the way down to -46.

In doing so, he pressed hard enough on the volume knob to go into the Hijack menu, which was at the "Set Volume Level on Boot" line, apparently the last thing I had ever done in Hijack, years ago. He then pressed the button again, either accidentally or trying to get out of the menu. Bingo! Set volume to current level.

Additionally, as you suggested might be the case, the player was in A/C mode. Since the player lives only in the car (I have no in-house system I could even connect it to) this is not a problem, it seems to work fine that way. But just to be sure, I went further into Hijack and set the Force DC/Car Mode to be DC.

Now all is right with the world.

tanstaafl.

More likely the mechanic pressed the knob thinking it would turn off the stereo, since that's the way most stereos work. When that failed, he tried a long press, and the rest is history.

An advantage with the DC/Car Mode, is that it will also auto-dim the display when the dash/instrument lighting is on (at night). And it saves the dimming levels separately for the two (day/night) modes.

Cheers