C-GORN, a Beech 1900D aircraft operated by Air Georgian, was conducting flight GGN7277 from Harrisburg Intl, PA (KMDT) to Toronto/Lester B. Pearson Intl, ON (CYYZ). During the flight, the flight crew noticed an acrid smell in the cockpit. As there was smoke associated with the smell, the flight crew donned their oxygen masks, advised the passengers of the situation and requested priority landing. Shortly after, the flight crew noticed that COMM1 was unserviceable. The aircraft landed uneventfully at CYYZ with ARFF standing by.
The operator’s maintenance confirmed the smell was from the COMM1 control head and proceeded to replace it. The aircraft was then returned to service.