Problem with added HRTF wav files on Steam Deck

[HaBe2305]

I've came to know (and will never leave again) the JDSP sink via the DeckSP plugin for Decky. Since the Virtual Surround Sound plugin doesn't work for me, I've copied the HRTF wavs that come with it to JDSP's irs folder.
They show up fine in the client, but do nothing audibly. Problem seems to be that they're missing channel and sample configuration - the info box says 'No selection' for all of them.
Hints on how to configure this for added HRTFs would be much appreciated.