Motorola SB6141 firmware upgrade

Hi all,
I am a new COX customer, just moved to Las Vegas from Texas. I have been using my own Motorola SB6141 cable modem over there for about a year without any problems. Unfortunately I can't get it to work over here with COX. It is unable to get a steady 'Internet on" green light and keep retrying to connect. So the installation technician 'forced' me to rent a COX Netgear CG300D modem/router.

I much prefer to use my own modem with my own router. I just read that my modem may not have the latest firmware in order to be compatible with COX. I also read that this modem is on COX's approved list. Here are some of the tech info of my Motorola modem:

Model Name: SB6141
Vendor Name: Motorola
Firmware Name: SB_KOMODO-1.0.6.3-SCM03-NOSH
Boot Version: PSPU-Boot(25CLK) 1.0.12.
Hardware Version: 7.0
Serial Number: 348781224820222308010001
Firmware Build Time: Aug 18 2011 10:27:53 

My question is -- what do I need to do to get the firmware of this modem to be updated by COX? Can I do it myself? Over the phone with a tech support person? or does it require someone to come to my home again?

Thank you very much in advance for all your help.