As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PILOT REPORTED SMOKE IN THE COCKPIT. INVESTIGATION FOUND THE (AUDIO AMP) CIRCUIT BREAKER POPPED. COULD NOT FIND THE DIRECT CAUSE. HOWEVER, THE RADIOS ARE ORIGINAL EQUIPMENT, WHICH MAY HAVE CAUSED THE SMOKE IN THE COCKPIT. (SO05200504849)