Static on cobra 29lx

If you have a ground wire running from your mirror mount to the frame, remove it. Its doing more harm than good.
After you remove the wire, see if the noise persists.
If it does, leave your radio settings normal. Unhook the coax from the back of the radio. See if the noise persists... If it does, the noise is entering the radio from the power side.
If you unhook the coax, and the noise goes away, it is entering through the antenna system.
This is just a quick test to narrow down where the noise may be coning from. There are only two ways this type of noise enters a radio..by the antenna..or by the power supply. By unhooking the coax, you are eliminating one way noise can enter the radio.

 

It would be interesting to turn the truck off completely when you hear the noise to see if the noise goes away Or try to figure out if maybe your phone charger could possibly be the source of some of that noise.

 

I just re-read the thread, @chriskc you say you can go all day and its fine? And all of a sudden the noise level will jump up, correct?

What are your surroundings when the noise level increases? Power lines, gas stations/trk stops, traffic lights, other trucks, being in town and alot of other sources generate rfi (radio frequency interference). This is something to consider also. Check all your antenna connections that they are tight, and free of corrosion.

 

Squelch definitely limits who you can hear

 

Wire will not work as an RF ground