Several of my devices with 3.5mm jacks make unreliable connections. The sound will cut out when the plug is wiggled slightly, or one ear will not have sound at all, or the sound will "cancel" in a way that seems to remove center panned audio but keep left- and right-panned audio. It seems to be a function of the jack and not the plug. Often it will get worse with device age.
What causes this unreliability? Also, bonus points for answering: Is there a way to repair damaged jacks and restore reliable connections?
Some guesses for why this might happen:
- Different manufactures have different specs/tolerances.
- TRS jacks don't precisely mate with TRRS plugs or vice versa.
- The spring mechanism (for tension fit) is located in the jack, so the jack tends to wear out faster than other connectors (compare to USB, HDMI, and DisplayPort, which put the spring mechanism in the plug).