It's highly likely that something along the line is damaged or not connected properly. I wouldn't bet on it being your "interface" though, its more likely to be the sound card if both input and output are producing the issue. It would be easier to give you some trouble shooting steps if you could provide additional information on your set up, as in all input and outputs and what goes into what.
To find the problem with this kind of stuff requires quite a bit of work, either way the first step would be to test your peripherals - as in your headphones and mic, plug your headphones into your phone and playback some audio to check they are working.
Then test the motherboard by plugging the headphones into that and playing back audio for youtube or something.
Then test the sound card by doing the same, then finally the interface.
By doing this you can work out for sure which part is causing the issues.
I hope this helps.
To find the problem with this kind of stuff requires quite a bit of work, either way the first step would be to test your peripherals - as in your headphones and mic, plug your headphones into your phone and playback some audio to check they are working.
Then test the motherboard by plugging the headphones into that and playing back audio for youtube or something.
Then test the sound card by doing the same, then finally the interface.
By doing this you can work out for sure which part is causing the issues.
I hope this helps.