I noticed something rather funny and cool today in the German coastguard map for RS: Siege.
There’s a room with a radio playing some kind of German song and for whatever reason I stood by the radio to actually listen to the song. I recognized the melody right away! This is the song you hear in “Das Boot” when U-96 first leaves La Rochelle early in the film. The only difference is that this sounded more like a Schlager song than a military march.