NMYSBH,
It really depends on the call flow and how your CO Trunk Group is setup. If the CO Trunk Group that the call came in on has Audio on Transfer to Ring set to Ring then that is what you get. If the CO Trunk Groups Music On-Hold is set to Use Next Device's Audio then you will need to look at what that devices audio for call ringing this device is set to; typically ring.
Thanks,
TE