Blackberry 9300 Mic Jumper Solution Repairing Fix
https://gsmfixer.blogspot.com/2015/09/blackberry-9300-mic-jumper-solution.html
Mic problem may occur due to water damage in your phone so you should clean the motherboard of the mobile with the thinner and CTC. Blackberry 9300 Mic problem can be solved by changing the mic with new mic. If the problem remains the same then apply the jumpers with jumper wire according the highlighted ways.
