it’s probably an issue related to the sample rate of the sound card that is not 44.1kHz (what Petaporon is assuming).
I had a similar problem in another project. I’ll try to have a look.
Sorry, I just saw your reply. Now I can't even seem to export it. It gets stuck on the loading bar of it "encoding". Very strange... Hopefully it works for other people though, and judging by the comments I think it is???
Sorry I can't be of more help! Thank you for trying to fix it.