If it is a factory radio, try disconnecting outputs from the radio one at a time - antenna, wire going to automatic antenna, each speaker output (disconnect one at a time). See if that stops the fuse blowing problem.

If it is a do-it-yourself non-factory radio (and wiring job), then VERY likely someone did not insulate the wire connections properly and a wire is shorting somewhere.

If there are other components to the radio elsewhere like in the trunk, try disconnecting those.