Have you tried reflashing with the latest firmware? Have you tried wired headsets or even bluetooth headsets/headphones for verification? Which shop told you that the board of your device had problem? Where did you source this device from and for how much? Did the seller tell you anything about the device? have you checked the device for any faults initially? Was your device working before? Have you overclocked your device and/or submerged the device into any form of liquid regardless of how big or small? Have you exposed your device to extreme/excessive amounts of moisture? Have you tried taking your device apart before? Has it been serviced by some technician whom you never knew of their reputation?