2001 Sunfire-no range on remote

I recently installed an aftermarket stereo with the required chime adapter. Ever since then, both door lock remotes have no range...only will work outside the window and in the car. They used to work 20' away. Would this have anything to do with the old vs new stereo? I know some functions like the chime used the factory radio. The antenae for the remote maybe? Is there an antenae for the remote under the dash that I buried?
Thanks