CM2050V firmware update

Believe what OP is referring to is the Comcast/XFINITY issue regarding compatibility with ISP's "enhanced speed" plans (mid-split setup).  You may recall that the CM2050V was on ISP list as a compatible, and recommended, cable/voice modem option suitable for higher upstream speeds in areas "upgraded" by Comcast/XFINITY. However the firmware update pushed out which allowed access to higher upstream speeds (V09.01.01) created significant stability issues for many other owners.  The FW for Comcast/XFINITY was then rolled back to older version V02.01.03 which removed the "access" to the higher upstream speeds.

In my limited contacts with each company, both Netgear and Comcast have pointed fingers at each other and though an earlier response to someone else on the topic made it sound like a FW update was being worked on by Netgear "with highest priority", the topic has gone completely silent on both Netgear and Comcast ends, leaving many owners $300 out of pocket for a modem that likely provides no discernible benefit over previous cable/voice modem.

So...voice works and the cable modem works, but only to access standard speeds and not to access the "enhanced speeds".  Neither Netgear nor Comcast are providing any updates and most threads seem to be closed down, and Comcast continues to push customers to "rent an Xfinity gateway" which most purchasers do not wish to do in the first place.