^ QA testing is a liiiiiitle bit different from producing audio.
You should probably read your NDA, because it's highly unlikely that you can't say anything
about it. If that's true, you've technically violated the NDA by saying that you did QA testing on any game. It would certainly make getting another job in a relevant industry interesting if you couldn't talk about your abilities in the context of your work.
I know a lot of devs who have worked on games and couldn't tell me which games they were working on... until they were released. But then they can say, "Yeah, I did the curtains in that game", or whatever.
Typically with an NDA what you can't disclose is the technical specs and other proprietary stuff.
But of course you can disclose that you worked as a tester. You can disclose the methodologies you've worked with, you can discuss the vendor technologies and softwares you've used to do the work. You can even talk about what kind of tests you were responsible for.
You just can't discuss the specific details about the projects you work on.
So yeah, read the NDA, as I highly doubt any game is so top-secret that you can't even mention that you've worked as a QA tester for company X who makes games like Y.
Anyway, just saw this in the OP:
Originally Posted by Orray
Due to strict NDAs on the projects I worked on, I wasn't able to save any of the recording sessions / samples.
If this is true, your only option is to ask ex-employers for copies and if they say no, just do some folio work.