Two DigiOnes play everything while the Signature just skips from one song to the next. All are running Roon build 167 and using DietPi v6.17.12 on the same network, with a NUC Core running build 363.
Have you tried power cycling the Roon core, and the DAC?
Yes, I found that shutting everything down solved the problem. Because rebooting my Signature did not work, I replaced it in the main system with one of the older DigiOnes. On a lark, I then connected the Signature to a secondary system where it began working again! I’m guessing that it must have needed to be completely POWERED OFF.