Chosen Solution
I have a Jensen UV10 car stereo. It has been working well, then suddenly I have no bass at all, (my sub woofers don’t work as well) while the highs still work. I turned off my subs, but still only have highs with no bass at all. Everything else seems to be working as it should.
Check the sub’s amplifier to see if it is still powering on. If the sub’s amplifier isn’t working, then you might be getting just highs and no lows because of the crossover settings in the UV10 or other amplifiers you have in the system. If your main speakers are running off an amplifier, then that amplifier might have a crossover setting that just sends highs to your main speakers. If your main speakers are running directly off the UV10 head unit, then go into the settings menu for the UV10 and disable any crossovers. That should send full-range signal to all the speakers that are working.
