Why does my ringtone switch midstream to a voice saying "incoming call from...."

[AC Question]

I have a Motorola Razr M and just recently all my incoming calls start to ring (very briefly) then switch to a voice saying "incoming call from (incoming phone number)". This happen regardless of the caller being in my contacts or not.

The most annoying part is I can no long silence the voice the way I used to be able to silence any of my other ringtones if I just wanted the call to go to voicemail without having to listen to it ring 4 times.