Correct firmware version for Cisco DPQ3212?

I've been having intermittent internet speed problems for the past month.  After 3 visits by Cox technicians, I am still having the issue.  The technicians have "improved" various things such as connectors, amplifiers, splitters, etc.  About a month ago the technician told me that since I have both phone and internet, I could get a free cable modem from Cox.  He gave me a Cisco DPQ3212 which worked fairly well for a while.  However, we have continued to have slow speeds, with the upstream speeds sometimes approaching *zero* during weekdays.  Very recently I noticed that my DPQ3212 was not bonding 4 upstream channels.  It would sometimes do only 1, 2 or 3 channels upstream.  I spoke with Cox Support today and we agreed that I should try a swap on the DPQ3212.  I swapped modems and things do seem to be a bit better; however we are still experiencing some (less severe) slowdowns.  The modem has (at least for today) bonded all 4 upstream channels.  I think that is a good sign. 

Enough about my problems.  Now to my questions.  I noticed that my first  DPQ3212 had newer firmware than the one I received today. The previous DPQ3212 had firmware version D3212-P15-5-v302r12901-110223a-COX (built on Feb 23 2011 16:13:10) but the DPQ3212 I received today has firmware version d3200-P15-5-v302r125573-20131008a-COX (Oct 21 10:08:39 2013).  Both modems report  a hardware revision of 1.0.  The only thing I can see that might be different is that the previous DPQ3212 reports itself as a DPQ3212C instead of just DPQ3212.  But the C might have just been added by the newer firmware?

Is the modem I received today running the correct firmware version?  If not, how can I get this upgraded?