Drivers Side Speaker Issues

[KIRIEIW]

I've been having issues with my drivers side kick panel/ tweeter speakers this past week and have no idea where to start diagnosing. I do know the kick panel speaker and tweeter are wired in a loop after looking at the wiring diagram so not surprised there both affected. I took the kick panel off to look if there where any breaks in the wires/ strands loose and saw nothing. This car is as stock as can be, absolutely nothing has been done to the wiring (or anything else on the car for that mater), not to mention how clean and tidy it is under the dash... factory fresh and a very high possibility it was never taken apart until I did today.

Now the issues I'm having..

The drivers tweeter/ kick speaker are sometimes cutting out, have a whine to them, and when you hit the breaks the speaker's pop (something to do with the brake light switch I'm assuming). Now when the speakers are cutting out on the car, its a quick "On-Off" style. It'll work for one second, and stop working for another second. There literally second pauses, so it may cut in and out 60+ times in a minute and continue doing this until you turn the radio off. Once you turn it back on, it continues. Other times they'll work just fine but the slight whining noise and brakes applied pop will still happen. Please keep in mind its only the drivers side speakers...

I have no idea where to start, any tips on what I should check to start diagnosing the issue would be appreciated.

[Das Delfin]

Check the connection from the front left speaker wire at the back of the radio

Also check out the radio's ground

[KIRIEIW]

I think it's something to do with the headunit. First off I noticed someone's messed with the head unit before, these two wires where swapped around. The wiring for the right side is suppose to be blue, while the left is yellow. Pictured in the pic bellow is after I swapped them to the correct sides. Also, when I swapped the two wires, the noise transferred over to the other side. I'm assuming its something to do with that specific plug in the head unit.

[StereoInstaller1]

If you swapped the blue and yellow and the noise changed sides, it's a bad deck.

Luke