My husband is trying to help an elderly friend.

Her Panasonic DMR-PWT560 has stopped sending any signal to her TV. The aerial signal is still passing through the DVR ok (reception of all TV channels on the TV is fine) and the DVR itself (and remote) are still working fine (the DVR recording light still lights up when it's time to record a programme and you can still use the remote and see the channel number changing on the front window pane of the DVR).

My husband has used different HDMI ports on the TV (and even a different TV) so it is not an issue with the TV.

He has swapped to a different HDMI cable (one we know works) and it is not the HDMI cable.

This makes him think it is the HDMI port on the DVR (or whatever is sending the signal to that port).

He spoke to someone with Customer Care at Panasonic who suggested a factory reset, but of course all of the instructions assume you have the DVR connected to a TV so you can step through the menus - but that connectivity is not working in this case.

So (a) would anyone know if it is possible to do a factory reset using the DVR window pane only?

and (b) is my husband on the right track in thinking that this is probably an issue on the HDMI output port (and if so have any suggestions for resolving that)?

Thanks very much.