Need help! Suddenly lost bass from all 4 speakers

[beaubbe]

The other day, while i was driving, I raised the volume on my radio (it was barely audible) and noticed that there was no bass coming from all 4 speakers. An hour before, everything was ok. I haven't had time to check what could be the problem. I just wanted to get some opinions before trying anything.
I have a dodge dakota sport 2002 with a pioneer deh-510ub headunit, a pair of phoenix gold 6-1/2" components in the front and fullrange in the back (con't remeber the exact model number of these). The speakers are powered by the headunit.

Like I said, I haven't had time to really try to pinpoint the problem. Of course, I checked all the settings on the hu (hpf is off) and everything was fine. I also tried reseting the hu by cutting off it's power but it didn't do anything. Since I lost bass on all 4 speakers, I'm thinking that there is a problem with the internal amp in the headunit. I don't have any other hu right now to try a swap and see if there is bass.

I was wondering of anyone had any ideas has to why I would lose the bass on my speakers.

Yeah, I forgot to mention that the hu and speakers where changed months ago and everything was find until the other day.

[Perry Babin]

It's not likely to be the internal amp. It simply amplifies whatever is sent to it. The problem is in the volume IC. If the head unit is under warranty, I'd suggest sending it back for warranty service.

Have you searched the net to see if anyone else was having this problem with this model head unit?

[beaubbe]

Unfortunately, the headunit is not under warranty. I've also tried searching the web for similar problem with this headunit or other headunit and haven't found anything similar.