Pressure on screen switches ring/silent. What to replace?

When "vibrate ring switch" is on "ring", applying pressure to the upper left corner causes it to toggle between "ring" and "silent". When switch is on silent it does not happen. Occasionally it will happen without pressure on screen toggling back and forth by itself.

Took phone apart per instructions "to replace vibrate ring switch" just to check for loose connections or dust etc. but everything seemed fine. Do I need to replace the "vibrate ring switch" or the "headphone jack and volume control cable" ? Or is this something else?

Thanks!