Sounds, as if you have/had a Steinberg USB Audio Interface in use. You could try and install an appropriate driver for the device. Otherwise I reckon your system tries to use this device but it is not the correct soundcard and/or not available. But this is just guessing.
Probably it is a good idea to post some more information about what OS you are using; also you should have a look at the log files and post what’s in there. On Windows you will find the
.sonic-pi/log somewhere here:
- Windows: C:\Users[username]\AppData.sonic-pi\log
- Windows: C:\Benutzer[username].sonic-pi\log
On Linux it is in you home folder and on Mac OSX I don’t know right now (could be:
Also it is quite a good idea to delete this folder alltogether. Maybe your preferences for Sonic Pi are somehow messed up. It will be recreated on next start of Sonic Pi.
Hope this helps a bit…