This might sound a bit random, but Cyberpunk 2077 has this sort of warmup sound that plays through the game startup sequence that always gets me relaxed or psyched up to play. Another example is the title song in Trails from Zero. Calms me every time.
Whether it’s a sound effect, music, or a loading screen, is there a game that does this for you immediately when you open it?
Mario Kart Wii (others versions too maybe) has a music with more and more instruments. The more you configure your kart, the more instruments are playing. It’s a nice warmup.