Missing weapon sounds

[Nickaura's Bane]

I formatted my machine today and re-installed windows 7.

Now my weapons aren't making any firing sound.
i can hear explosions etc , but firing sounds aren't coming out.


Everything was working fine before reinstalling windows.

2600k
8GB ram
w7 ultimate x64
R9 280x.

Can someone shed a light on this?
thanks.

[Nickaura's Bane]

This is happening on both Unmodded and modded clients.

[Nickaura's Bane]

EDIT.

I fixed the problem
if you re using 5.1 settings disable the frontal speaker.