Media transfer problem. Please help

Ok, So I had 4gb micro sd card for the longest time. I used it inside my smart phone, and had a bunch of music on it (around 350+ songs,) and i started running out of space.  My parents got me a 32gb sd card for christmas cause they heard I was running out of room. Well. I was super excited. I transfered all of my stuff onto the sd card, and plugged it right in. Everything was perfectly fine, until I went to listen to some music. half of the music files won’t play. the phone keeps saying “Sorry, the played doesn’t not support that audio file” and I know all of this songs played just fine the other day when I was using my 4gb. I’ve tried everything I can think of. Loading it straight onto the phone with the sd card in it, scanning the sd card for ploblems, and fixing them, formatting it to fat32, listening to all the songs on my computer to make sure they are ok (all play fine on my computer.) I’ve been spending almost 3-6 hours straight for 2 days on this. I am so tired of it, and it’s really beginning to be a real pain… 

What am I supposed to do? Thank you to anyone who replies, every bit helps. :slight_smile:

What is the source of these files that won’t play on the new card? If they were DRM-encrypted they would play fine on your computer and probably on the old card, but not on the new one.

Are they .mp3 format, or .wma?