(Audio Issue) so… I’m in a bit of a pickle here…

I lost all my music after reinstalling Windows 7, and now that I’m redownloading it it sounds wrong.

After using System Restore it unistalled a few updated files which damaged my PC, it couldn’t even start up. thankfully I found a method to go back to the last functioning session so I did that to start up my PC and use it but the system was imcomplete. I could see/listen to any files (like music, video, images, word files…) but for some reason I couldn’t enter to the Internet and no trouble-shooter wanted to work, I tried to update but there was no hope, Windows Update was dead too. so I had my 200 albums of music intact, and all my other files and program too but if I wanted to keep them I’d had to sacrifise my interaction with the Internet, no disc in hand to repair it since my cousin was the one to install me Windows 7 before with a pirated disc, so I was left with no other option but download a Windows 7 installer with no password with it, on one of my blank discs and so I did. I saved some of my songs (which are the reason I started to notice this issue) and installed Windows 7 used RemoveWAT and Chew-WGA to make it "official".

So there they went. 200 albums, most of them soundtracks some of them songs. and here starts the real issue.

Since my music it’s really important for me I tried to redownload it (a pain in the ass but it’s worth it) but here’s the thing… everytime I download music it sounds… off? wrong? I mean… I know MP3 it’s lossy but… constantly changing the music stream? even I know MP3 has some consistency on it’s quality. I don’t know why but when I download music now it’s downloaded wrong, it’s barely noticeable but upon making side-to-side comparisons with songs that I managed to save but downloaded again to do doble-check, by using the same websites I used to get them before; and as I said before the stream it’s different, it’s a bit lower and the sound quality sounds… kinda off, meanwhile the files I had before do sound as clear as water (at least as for MP3 quality goes).

What pisses me off it’s that my old files all do have stereo yet the new ones are being saved in joint stereo which I don’t understand why that is. and to make things more confusing it’s that the file size it’s the same in both files (example, messy file and old file both only ocuppy 6,77 MB of storage) and both have 320 kpbs. and before reinstalling I used to tag and put images on the files and their file attributes would remain the same (Attribute: A), now if I do that I think some files get corrupted down the line of the process ‘cuz afterwards some of them will sound flat and the Attribute changes to AI which I don’t know if this change of attribute could be the reason for it.
I have a few guesses:

1. Windows 7 didn’t really become official to begin with. I was warned by the system that not putting a serial key would restrict me from ”fully enjoying Windows 7” perhaps the system it’s doing this shit to me on purpose.

2. the drivers are all messed up after reinstalling. but the thing with this one is I already Updated them twice, first I updated the built-in HD Audio driver or whatever it’s called, and then I upgraded to Realtek yet it seems prominent.

3. perhaps the speakers affects the way the music ends up being? it’s that even possible? ‘cuz I started to notice this after I added a new power cord to my speakers. yeah it’s a stupid thought but I don’t want to roll anything out.

4. life hates me :(.

if any tech fanatic out there knows the true reason and could help me out with this I’d be so gratefull.