From what I can tell the GSM codes are network errors and for one reason or another the TiVo’s VOD request is being denied. It could be something on your end but most likely it’s on the Comcast network side. They updated something and left out some of the old config or something in your account as it must have the special TiVo Premier VOD code added. I had GSM-11 (only after reboot) then GSM-7 on my TiVo for the last three days after everything had been working fine for over a month. Comcast by default, wants you to reboot everything, replace everything, resend the pairing to the CableCARD, send a truck out and so on. Anything but escalate the issue the tier 2 or network guys and start a trouble ticket. I had read up on it a bit and kept pressing for a trouble ticket and telling them they can send out a truck and make me replace the CableCARD but everything I’ve seen on line says it an issue on their network. The last guy finial started a ticket the other day and today it magically works again, no reboots or replacing cards or clicking my heals together three times and so on.