Galaxy s3(i9300) sound/reboot problem, need and opinion

Daniel Tom

Estimable
Dec 15, 2014
2
0
4,510
Hi, i have some problems with my galaxy s3 (i9300) international version. I don't have a warranty.
Android version: 4.3, stock
Problems:
-keeps restarting (very often)
-no sound at all, speaker or earphone
-microphone not working (not working in call, google now said that cannot connect to microphone)
I tried reflashing stock, same problems, i tried 3 custom roms including cm11, same problems. I cleared cache, dalvik, wipe data, nothing changed.
In my noob opinion, i think the motherboard is the problem, i don't think it's a software issue after all i've tried, but before i order a new motherboard for replacing, i would like to hear other opinions.

Thx in advance.