Nope, I'm using free accounts on both spotify and soundhound.. However, I'm still waiting for my playlist to get updated, so not actually sure it works 100% yet.. But at least SH claims to be connected now 😄
edit: yeah, OK, so it won't automatically update the playlist with my old searches, but new tracks do get added..
but if you're already logged in, and it's still not working, that probably doesn't help you anyway..
tried removing the app and then reinstalling and reconnecting your accounts?