First, I know this question doesn't exactly belong here, but I'll explain later why I'm asking here instead of on the specific android board.
I'm developing an app, and yesterday I had some problems with sqlite, so I went on to checking how my database looked like. Found out I didn't have the sqlite3 actually installed on my phone, so I followed this answer to install it. I got some problems with the pushing part so I tried to alter the permissions on /system to try and make it work. I basically ran "chmod 7777 /system" on an adb shell. After that I still couldn't push the sqlite to the phone, so I quit the shell and tried to open it again, but I got a no permission error. When I unlocked the phone, every possible app (including system ones) started crashing, one after the other. I freaked out and took the battery off. at that time I had the phone connected through usb to a Ubuntu pc, with no headphones connected. When I turned the phone on again everything seemed to work properly, and I managed to push the sqlite to the system folder without any problem. I thought the problem was over and moved on with debugging and developing.
When I was going home, I was listening to some music with headphones and a friend called me. I answered but couldn't hear anything. I then later discovered that since then I can't hear anything and no one can hear me too. Every other sound related function works fine, except calling. I'm not hearing even that calling beep.
So that's why I'm asking here, as it's actually a question related to developing and coding stuff. Please, if anyone knows what this might be, answer here, I have tried many things to get it working again, but none of them worked. I read it could be a headphone related issue, but that seems to occur only on some motorola phones or something. I have a Galaxy S advance, 3 or 4 months old. I have also tried to change the chmod setting again, to chmod 4755 /system, but it remains the same. I'm getting really desperate here, I don't think customer support can solve this.