I had the down vol stuck. Now the up vol is stuck and always shows vol 30 on the screen. I have the phone apart. Shot the hairdryer at it in case it was water. Anything else to try before replacing the button strip. Anyway to tear into the vol. up button?
I've just fixed the same issue and want to share my experience. In my case the problem was in the flex cable. Apparently, I damaged it while changing a digitizer. I assume that I could have bought the cable and replaced it, but since I was not sure in the source of the problem I simply cut the piece with the volume up button out of the flex cable. Now everything works! Volume can be controlled with an app. I'm fine with a little bit crippled phone.