I favor a small cylindrical earbud with a good seal inside my ear for use with the amateur radio on my bike. These things come with back vents that allegedly improve their bass response; that’s not a concern for communications-grade audio and, worse, the vent produces a tremendous amount of wind noise.
The solution is straightforward: put some tape over the vent!
I used Kapton tape, because I have it, but in point of fact the snippet of duct tape I applied on the first ride (having forgotten to do it on the bench) worked just fine. A drop of epoxy would be fine, too, if you were a bit careful about not letting it ooze down inside the case while it cured.
Despite the fancy appearance, this is a random pick from the assortment of earbuds I’ve bought at $10 or less over the last few years. According to my golden-eared assistant, the audio quality varies dramatically among the assortment, but they all work reasonably well between 300-3000 Hz. I suspect the insanely cheap ones on eBay are essentially the same things, although IMO they’re intended to collect large quantities of high positive ratings: caveat emptor.
Speaking of caveats, insert the usual safety caveats here.
Note that we’re using one earbud for tactical comm, not boppin’ to the music, and the audio level is low enough we (well, I) can’t hear diddly at speeds over 15 mph. Your jurisdiction may prohibit “headphones” or “earphones” or some such, so behave accordingly.
All the officers I’ve met think the radios are a great idea, if that means anything.
The Smell of Molten Projects in the Morning 
Ed, get yourself a few sets of Griffin “earthumps” on Amazon.. now going for 4$. Value for money.. I use them for everything around. Seals well, comes with three sizes ear cushions and a pouch.
They look good, but shipping costs more than the earbuds! Worse: buy two and pay twice the shipping … even though they’ll surely arrive in the same first-class envelope.
I’ll keep ’em on my list for a free-shipping day!