Thanks for taking the time to help out.
For Kind, they say: Apple MPEG-4 audio. And Extensions are all m4a's.
But this is after I've deleted all of them and downloaded all the memos from my phone again.
So now what I actually have is fine. The new issue that surfaced is that not all the memos from my phone were uploaded to the computer and I have no idea why.... I'm getting really tired of 'There's always a new issue popping up' and I'm sorry about this but if you could give me a hint as to what to do about this, how to get all my memos to be copied onto the computer, I would really appreciate it.
Note: Also, the conversion, I'm just gonna use iTunes to convert them into AAC files. So now they do appear in my phone's music player! Initial problem solved and thanks for that!