You can find some old fw here:Can anyone please share an “update.hex” file for CM (not CN version). I am having issues with DSD files freezing or not playing at all. I’d like to refresh the firmware in hope to fix the issue.
https://www.head-fi.org/threads/new-tol-a-k-dap-the-ak-ultima-sp1000.850061/post-16171186