Please share the client version and setup box line. Move to the right to system resources and look at disk usage on the bottom.
Also which channel, show and time are you having trouble with?
The hardware information identifies which version of the stb you have while the programming information let's others check if it is a guide error.
It also won't hurt to pull the plug to the PVR and have it reboot. If there is a system glitch doing the reboot should clear it out when the software reloads.
If its as Fossil suggests, a guide issue then the reboot will not fix that as the problem is with MTS's provider of the programming guide.
The STB are all computers running a specialized version of Windows.
That said, to reboot you can hold down the power button on the box for approximately four seconds. I also think there is a menu choice under the systems menu to reboot the box.
If you do unplug it would be recommended to unplug, wait about ten seconds and then plug it in. The PVR does have moving parts inside, ie the hard drive, which could get permanently damaged if restarted too quickly, although that is a very slim possibility.