if not then try a reboot (off then on). You could try home-thumbs down-thumbs up-play-play which I've tried but it only cures it for a few hours at best. I'm sure the mod will be back with more suggestions
I've run a diagnostic on your TiVo® and there's an issue there with the Input signal. Although it's unlikely this would cause problems with slow speed when navigating the box, it can cause issues with iPlayer and possibly channels (if left to get worse).
I've sent you a private message (purple envelope at the top right of your screen) so I can arrange an appointment for a technician to investigate.
Look forward to hearing from you.
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