Okay, soooo you've guys used pretty much the same stuff since... well... almost every WW2 game you've made. So... some suggestions are in order because this is my one and only gripe about your games, IT NEEDS AN UPGRADE IN THE WORST WAY!!!!

I understand your a smaller developer, you don't have access to the best and brightest music guys, you don't have a ton of money to waste, so you recycle everything and anything you can. I understand that, really, I do, but you still need an upgrade. So, have you considered switching to Classical Music? Bach, Mozart, Beethoven? Not a lot of copyright issues with them, so I'm pretty sure they're free to use. It works for WW2 style games since most of the composers were German.

If Classical isn't your thing, have you thought of period pieces? Some examples:

https://www.youtube.com/watch?v=I1d2a2JyEdw
https://www.youtube.com/watch?v=gcrtodO88qM

Some songs could be made to only activate when a country is being played by the player: Russia has some great WW2 songs, my personal favorite is below.

https://www.youtube.com/watch?v=kr3qMORtM5M

Just some idea's. Please... if you do build another game, keep this in mind.