I don't prefer any earbuds in my ears while riding. Force of habit I guess from growing up riding in a congested urban (NYC) setting. Need to be very alert.
These days, I don't enjoy the sound of vehicles rushing past me....but I rather hear them approaching than focused on my favorite tunes.

While wrenching, the MP3s are always playing in the background. I listen to jazz, 80s( synth pop, brit bands), and vocal trance. Oh, and Car Talk on NPR should it be on at the time. Those guys are hilarious.