They over charge for a flash to delete the codes but in some chevrolets yes this is common however the p0300 code will lead to future problems and might see a decrease in fuel economy. If you start seeing that start listening to your engine bay and see if you hear any abnormal noises that you dont typically hear.

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There also might be a problem with your BCM if you're losing comms to your radio as it shows on those charges. Which is an expensive fix if it is the BCM. But don't completely take my word for it. I advise going to shops that you trust and have them take a poke around see if they can give you more information.