While connected to Comcast Extended basic (analog), I receive some HD channels (those that are the locals). Of late, I have noted that after a while changing between HD channels yeilds no change in the HD Program. For Example, If I were to select ABC HD, all HD channels would show that programming. My firmware version is 1.3.5 and the latest is 1.4.5. Has anyone had this problem and/or do you think the firmware update will improve matters? Tnx for the help.