Strange MP3 issue

Hi,

First off, I'm a noob when it comes to some of this stuff so if I've overlooked the obvious, please forgive me, but I'm at my wits end as to what to do about a problem I'm fighting.

I have a set of 9 mp3 files that are a low bitrate mono recording of someone speaking. When I load them onto my Android phone I have 3 different players that won't play them (MediaMonkey, Spotify, and Emby). However, VLC and Samsung Music will both play them, and the play fine on my desktop. MediaMonkey errors with "Missing Codec" and from what I can find online, the sense I get is that these files are encoded in some way that the codecs can't figure out. To try to fix this problem I've used ffmpeg to convert the files to a WAV file and then back to a MP3 file thinking surely that'd resolve any codec issues. Still not working.

ffprobe returns:

Input #0, mp3, from 'output_compatible.mp3':

Metadata:

encoder : Lavf58.20.100

Duration: 00:38:02.14, start: 0.025057, bitrate: 192 kb/s

Stream #0:0: Audio: mp3, 44100 Hz, stereo, fltp, 192 kb/s

Metadata:

encoder : Lavc58.35

I do realize that this encoder might be older, but it works fine with other files I've manipulated with it so the issue isn't with the age of the encoder. Any insight as to what might be the issue, or other things to try would be most appreciated!

TIA