When I turn the volume up it starts turning it back down by itself?

Take the batteries out of the remote or cover the IR emitter to determine if the remote volume button is the problem. If not then check the button on TV utself to make sure it's not stuck

The main system control memory IC to this TV is damaged. Replace it. If you wish to get some details; visit the site linked here. Pull up older posts. Surf the site with patience. http://electronicshelponline.blogspot.com/

Have you owned this car since new? If not, when did you buy it and in what condition?

I've got this problem these fixing only work for a sort time! Volume just turns itself down?! Anyone no the real fix?

speaks are hooked up wrong or speakers are blowin.

most likely a defective volume switch on the handle bar

maybe defective speaker or audio output ic or shorted capacitor within audio circuit

Bump

Enasni,
It's probably a tact switch problem, something we call in the industry awindex syndrome. The tact switches, depending on the ones effected, can turn the tv on/off by itself, channel +/- at will or in your case control the volume.
Tact switches are not expensive to replace but a bit difficult to get to if you're not trained. They are at the very front of the board - looking from the back - and some disassembly may be necessary to take the main board out.
A reputable shop wouldn't charge much do fix this problem, switches are about a dollar a piece.
Good Luck
Bill