What you're after is impossible..
Earbuds with good sound, will be isolating (to provide bass) and have a thick cable (to prevent movement of cable while seated)..
HOWEVER, if you're ON the GO.... the cable will create loud Thuds; when it brushes across ur cloths/ shoulders, when you walk heavily, your feet, your body will generate thud noises as well while wearing isolating earbuds
The only type of earbuds that DO NOT have the cable-thud sound, are non isolating.. and they also sound like crap.. and they also DO NOT cut out factory noise..
So you see.. what you're after does not exist..
UNLESS you can accept cable-movement noise, and / or really crappy sound.. to which why bother listening to the radio at all.