Samsung Galaxy S4 - voice recorder file was there, played fine and now vanished

I recorded half an hour of dictation on my phone voice recorder app this afternoon. I played the first few mins of the recording and it was fine. I changed the name of the file from "voice 001" to something relevant "emma". Now I cant listen to the file!

The recording is still listed in the app, but when I tap it nothing happens. It still says 25.38 for the duration, but the size says 0kb. I've sent it to sky drive & drop box and same thing there....it wont play.

I go into the storage card/sounds file I find it as "emma.m4a". when I click on it I get to chose either Google play music (this says "sorry can't play track selected") or sound player (this says "sorry the player does not support this file type").

Does anyone know what's happened and how to get my recording back? Please! I'm going to be so gutted if this file has vanished

I'm hoping someone replies to this thread because I'm now afraid to try the voice recorder until I know it won't be time wasted.

There is a discussion here with several repair options to look at. I hope one will work for you:

fixing a corrupt mp4 audio file.

On another note, I've used the app Smart Voice Recorder many many times with excellent results. It's like the basic voice recorder on steroids, with many options...

https://forums.androidcentral.com/e?...token=-53h1V3p

All my voice recording files were deleted. I remember deleting the cache hoping it would clear some unwanted files but it looks like it deleted my voice recording files.
These are very important files for me. Does any one know how to get back the voice recorded files. I tired Dr.Fone, Remo recover and Asoftech data recovery tools but of no use.
Please help

Exactly the same thing recently happened to me. 20 files disappeared with no explanation.

Been onto Samsung for an hour and they are basically clueless as to where the files are - deleted? hiding? Moved? take your guess...

(and before anyone says i should have backed up, well I can't because of the ongoing issue with Windows 7 not recognising the phone when connected - can't install the MTP driver - another known issue to Samsung that their helpdesk people can't solve)

I did in fact back up my old S6 phone with recordings on it. I used Smart Switch. So when I restore the data to an S7, I notice the recordings are gone. I have no idea what happened. This crap is unbelievable. Had I known this, I would have moved the recordings off the phone onto my PC.