Facing TV Problems? Ask a TV Technician.
If Timeshift is started with Play or Pause key, the Timeshift is sustained until the Stop button is pressed. In case when the Timeshift operation becomes not available (such as switching to another application, an analogue channel or changing the input source), Timeshift stops without a notification and will resume automatically as soon as the source is switched to Digital TV.
Try pressing the Stop button to stop Timeshift, then try starting the recording again.