I got a sundown saz-1000d in trade.since dont have any subs yet i unhook my four channel amp to see if the amp worked. when i turn my radio on the fuses pop.i only hook up the power and ground the remote wire and the rca up.i was thinking it could be doing this because im using 8ga wire and i have a 80 amp fuse under the hood. when i hook my four channel amp back up to the same wires it works just fine. i went to the part store and to get my fuses and everyone pop on me.i replace the fuse with 25 amp fuses.what could be causing my fuses to pop?

Are you talking about the fuses in the amp? If so time to send it to db-r electronics to get it checked. You could also pull the back cover off and look in there if you know what to look for.