Perform the following steps:
1. Close Onyx.
2. Rename the Onyx.INI file to Onyx.ini.old.
3. Start Onyx.
No Onyx will generate a new INI file with the default settings for
it to work. If it still doesn't work, ensure that there isn't more than
one USB soundcard connected to the PC.
Now you can compare the INI file and change one setting at a time and
start Onyx again until you find out which setting is causing the problem.
Make sure that screen position items are never edits by hand, Onyx will
always manage those settings.