From the store page, under “Documentation, support and returns”:
In addition to the standard 1 year EU warranty, we’re also giving a one-month no quibble return for all units. Test the OSSC in your setup and if it doesn’t work, return it to us for a full refund. All we ask is that you pay return postage and send the complete unit and any accessories undamaged.
So if you bought your OSSC within the past year, it should still be covered, and you should contact BuckoA51 using the VGP contact form; he will have more details.