New Phone equipment - Voice and Data Modem TECHNICOLOR CGM4140COM

I was sent a new  modem to swap out with my old voice modem.  they sent me aTECHNICOLOR CGM4140COM which looks like its for their x-fi servicei.  I only need a voice modem since I have my own cable  modem.   I am hoping they can just active this for voice and leave my cable modem alone.  Does anyone know if this can be done.  I don't want to start the process and have it messed up.   The last time I upgraded  it was my cable modem and it wasn't a pleasant experience