If you did a complete recovery to out-of-box state as we discussed in your other posting and the sound still does not work, that means a hardware failure, not software. However, if you want to give it a try, HERE is the audio driver for your machine. Installation instructions are included at the link I gave you.
C.B. Toshiba Sat. L675D-S7016 Win 8 PRO 64 Bit---Toshiba Sat. L775D-S7132 Win 7 PRO SP3 64 Bit which also has Virtual Machine with Win XP SP3---Toshiba Sat. L305-S5921 Win Vista SP2 32 Bit