When dust or other foreign particles get inside a tuner assembly, it can cause several problems for the radio. The dust particles can interfere with the mechanical movement of the assembly, making it difficult to tune the radio to the desired frequency. This can result in poor reception or a loss of signal altogether. Dust can also cause electrical problems in the radio circuit by increasing the resistance of the assembly's contacts, resulting in a weaker or distorted audio signal.
You can remedy this by rotating the tuning dial back/forth across the complete frequency band multiple times (Approx. 10 times). Though, in some cases where the dust or debris has been in the radio for some time, a technician will need to dismantle the radio and spray compressed air into the tuner assembly to blow out any loose particles.
If this procedure doesn't improve the performance of your radio, please contact us for more assistance.