For WWII Movie buffs I have over 100 movie theme songs that you can downlod.
They are post war and not historically correct for radio or gramaphone.
To help with those long boreing patrols I do have some of them on my gramaphone (shame on me but I love war movies). The rest I play in the background while I hunt. There are several submarine themes including Das Boot.
http://www.subsim.com/radioroom/downloads.php?do=file&id=1231
enjoy
LZZ