Hello, It's hard to say for sure of course depending on what type of transistor it uses, and availability but the average cost would be roughly $25-$30 per transistor and labor to replace them and re bias the unit would be close to $125 or so. You could be into the unit for over half of what you paid for it. I honestly would not put the money into the Sony as they are known for this problem happening. My recommendation would be to purchase a Yamaha as bar none, they have the best price performance ratio and also the best reliability in the field in this price range.
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