Hello. First corvette ever. 1999 convertible. Dealership I purchased it from said the radio was causing a parasitic drain which was causing the battery to drain. Has anyone experienced this before? If so, is replacing the radios the only fix? Appreciate the input.

 

Welcome to the forum.
Before I replaced the radio, I would pull the fuse and see if the parasitic drain goes away.

 

Or, check your glove box light. I also have a 99 and it's our first Corvette. I had a new battery, which I installed, drain dead over the end of last winter. After doing a search, I came upon some information regarding a parasitic drain. Two places that were recommended to me was the hood light and the glove box light. Sure enough, it seems the glove box door may loose its shape and when it is closed it will not push the switch in enough to turn out the bulb in the glove box. Once I remedied that, I no longer had a battery drain. Look to see if you can notice any light around the door of the glove box coming from inside the glove box when the door is closed.