Crossfire CFA602

Did you previously replace this transistor? If not, check it and replace it if necessary.

Are there any bad solder joints on the emitter resistor it's connected to?

Is the emitter resistor out of tolerance?

There are two connections to the emitter resistor. One terminal of the transistor will connect directly to the emitter resistor. The other connection will likely be through a resistor (but could also be directly connected).