Motorola Razr with bluetooth headset.. why is my ringtone different?

Hey, I tried looking on motorola's website, but it wasn't much help and maybe someone out there knows what to do. I have a motorola razr and I just got a plantronics v510 bluetooth headset.. I have always had a custom ringtone on my phone.. now, if I have the headset turned on.. when someone calls, it gives me a generic ring tone. Where can I change that?