I bought brand new 6x9's (Pioneer 3 way's) sound pretty good for the price(wasn't going to kill myself right now with speakers) but the driverside rear speaker cuts in and out while driving. It's not the speaker because it happened with the old ones too. Could it be the wiring? Please help.

 

probably the wiring.. double check the connections and make sure the wires arent being pinched by anything.

 

Most definitely a wiring problem, the vibration is bouncing the frayed/shorted wire in and out of contact.

 

You didn’t say if it was the stock HU or not but it could also be a bad connection in the HU. But not really all that likely.

 

it is the stock head unit but i just got the car and im planning on getting an aftermarket one, just making sure its the wiring because i'll have it all done over in that case.