I recently purchased a Cisco PVR. I cannot set the Power On Channel as per the last PVR. In addition, it will show the keyed in numbers but will not place them in the select the Power On channel box. The current setting Disc (channel) is selected and will not change even after Saving the channel I wish from the drop down box.
I'd like to help with the issue you are having. Have you tried to use the side arrow keys to change to the desired channel when the box appears instead of keying it in manually? If it doesn't work, try unplugging the power cord of the box and plugging it back in after 10 seconds, then go into settings again. Sounds like a glitch. I tried replicating it at the call center here but it's working for me. Let us know.