Optiplex 760 Audio Output issue

Hello,

I have recently obtained an Optiplex 760 MT, and while just about everything seems to be working fine, I am running into an issue with the audio.

Both audio output jacks, both frontal and rear, don't seem to work. The microphone jacks both work, as do all other ports on the Optiplex.

I have tried updating both chipset and audio drivers, various devices, and confirmed that audio is enabled through the bios.

Any help will be much appreciated!