Gene this is a great question,
It seems to have alot of "solutions" too. But none are 'definitive', actually that shows nothing really works for everyone.
Do you wear ear plugs? can you har your starcom ok? do you always use your starcom?
it become difficult if your existing audio (assuming you have one) isn't in use all the time. I tried in ear speakers but without music they didn't give me the noise reduction I wanted.
Helmet speakers would be great, if you had some you could hear over the ear plugs. then just put the radar detector through that.
the visual alerts do work. I've gotten used to the Marc parnes I have. At first I kept looking at it, it was distracting. But not after awhile. You realize you will see it because it's in your peripheral vision, all the time.
Good luck with it! kind of a pia on a bike,