I had plenty of issues with a cheap USB sound card I bought. I wrote about it here and here
later I borrowed a Presonus USB 96 sound card from a friend and it works just fine. Pi 4 is recognized it at start, as well as pd. Is there anything wrong with using that card with pd and Pi ? it should be part of installation running for around 3 months.
Also - how can I make sure pure data is choosing that card on start?