weird noise of 6150

I flashed 6150 of my friend with same p5.23 flash that i have on my phone too. After flashing there were "contact service" on the display, but only for 2 seconds. After that all went normal. I updated faid and reseted sw as normal. Now there is one serious problem with that phone: Any sound coming from speaker is very cracked. (Ringtones are normal becouse these don't come from speaker.) When calling i can hear if somebody is answering but i can't hear even speaking becouse of that whistle and rumble.
Any ideas how to fix?

go to settings den restore factory settings. 100% worked for me

bisdak:D

NokTool didn't help but Wintesla saved my life!!! ;) (phone wasn't mine...) Thanks anyway!