First question to ask is if the radio is off frequency, and the counter is simply reporting it to you. If you can hear the channel you should be hearing, that points to a failure in the counter. And if you can't hear anyone on a channel where you should be hearing them, the radio's PLL circuit has lost its grip on the channel frequency and the counter is working like it should.
If it's over 20 years old, the 10.24 MHz crystal could be the culprit. They have used a higher-quality crystal since those days, and this failure is not as common as it used to be.
Soldering failures in the front corner where the PLL is located are very common. We see a lot of radios with that circuit board with soldering faults.
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