Hi there. I cannot technically answer the question, but I do know that it is not just the sub which matters. It also depends on the quality of the whole system. The amp needs to be powerful enough to provide the speakers with the sound, otherwise if you turn the volume up too much on a fairly low powered amp it with simply become "muffled" and unclear. Good luck in finding the answer, and then being satisfied with the sound.

Richard

Audio shops don't charge all that much to do an installation , You'll know it's done right and you won't have to experiment and learn on your own vehicle .

My truck is simple so I did my own but when the ole lady wanted a double din in her Accord , I took it to the shop .

Update : I have a pioneer 5.1 surround sound system and music only plays out of the right half,sub and centre..theres a lot of different settings i can set it to and i was messing around trying to see if i could fix it and when i put it on action or sport or any channel like that the left side ecos.

they are set up right because i did a test on them and there was white noise coming out of every one of them

its not the aux cause this is the second one iv bought

What is s a good 2 channel amp , that is fairly cheap,and can connect to a pc that can handle the following 85w speakers?

Hmmm. Worst case scenario is possibly a loose connecting within the head unit itself, which would require pulling the unit out, checking connections, re wiring and/or resoldering.
The other one I can think of would be the input jack has been pushed in and is recessed slightly, making it seem deeper than it is.

Best Case? Maybe there's junk in there. Get a can of compressed air and try blowing it in the hole...*clears throat*...
But, DONT blow full force directly into the jack, sweep the can back and forth while applying the air.

If the cables and the actual MP3 player/phone are both good, I can't think of what else it might be. Good luck!

(As far as exactly how to repair the aux if it's loose is definitely something I would have an audio shop do, unless you have a warranty, or, you are feeling mighty DIY. You can find repair manuals online. Shop might charge $50-$100. Basically paying for labor. Some mechanics would do it also.)