Why does the earbud audio cut out when I press the Home button?

When I press the Home button while my earbuds are plugged into the jack, the audio will usually cut out in the left earbud; I think the right earbud may become momentarily quieter as well, but I'm not sure. This also sometimes happens when I put pressure on certain parts of the screen near the home button, including when I walk with the phone in my pocket. There are no interruptions in either phone speaker audio or Bluetooth signal when I press the button, and I have not noticed any interruptions in the signal through the jack when I am not pressing on or near the Home button.

Also, my phone no longer responds when I press the remote button built into the earbud cord (above the split, on the left side).

I have tested other phones with these earbuds after these problems started, and have determined that the problem is within the phone. I would prefer to fix this without having to replace the entire jack+Lightning connector assembly, but I haven't opened the phone up yet so I don't know for sure what's broken.

I have replaced the lightning connector assembly, which fixed the problem. However, errors during the repair have led to new, more serious problems which I will detail in another thread.