The lack of answers suggests “nobody knows”.

I’d forget about it and hope no more recordings behave the same way.

But, if you can’t…

I notice the photo shows the broken symbol and NEW. Were these recordings playable? What error was displayed when you first tried to play?

I suspect something has corrupted the set of files that make up a recording. One has possibly been deleted and the others remain, confusing the Humax.

You could try a factory reset. (You’d lose all your timer settings, so make a note, and you’d have to retune. You shouldn’t lose recordings – make sure you don’t do a format). It might just free up the file (unlikely!).

Alternatively, try the HDD Test, it might discover something(probably won’t, let alone fix it):

[F] Settings/PVR Settings/Storage/Internal HDD/HDD Test.

If nothing else works, I really would just leave it.

The only sure way to remove the files would be to format the disk – losing all recordings you have.

A1944 – 22 hours ago  » 

It wouldn’t have been playable with a zero length (2100-2100).

Oops. Didn’t look at the mage that closely.

Can’t remember what causes zero length files. A crash?

I can’t think of any good reasons for it not being deleted.

Apart from my previous suggestions, the only other option is to power off the Humax. Turn off using the remote when no recordings are in progress or due. When the disk has finally stopped operation pull the plug and leave for a few seconds. Then plug in again and see if there is any difference.