If your boyfriend had the jumper cables running from the negative of his car to the negative of your car and positive to positive he did nothing wrong. The plastic on the jumper cables often get very hot especially if your car was stone dead and the jumper cables are thin and light duty. ( cheap cables, in other words) If your car runs fine I doubt the jump start had anything to do with the radio going out. Check all the fuses under dash and under hood with a 12 volt test light and key in the on position. Most radios have 2 fuses, one for power and one for memory. If you know how to use a test light or know someone that does this should be your first step. If this doesn't work then a trip to the dealer is needed.
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Regards Gunny44
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