The IEMs should fit like a glove. Definitely get a new set of molds by a different audiologist who has experience with musician's plugs. When pouring the goop into your ears, there are different sized wedges they will insert into your mouth depending on whether you will be singing with the IEMs - or not. The opening of your mouth will affect the tightness of the ear canal, and corresponding dimensions of the IEMs. Be sure to factor that into the process.
In 1999 I had a set of Westtone musician's earplugs made and used them all the time - not just for music, but underneath sound reduction earmuffs when I'm mowing or shooting. Two years ago I noticed the fit had become loose. Apparently they shrank or my ears changed. At any rate, I went to the audiologist and had another pair made. I suspect this will also happen in 5-10 years with the IEMs I got last year. Just a cost of enjoying the benefits - like having to repaint the house every so often.
In 1999 I had a set of Westtone musician's earplugs made and used them all the time - not just for music, but underneath sound reduction earmuffs when I'm mowing or shooting. Two years ago I noticed the fit had become loose. Apparently they shrank or my ears changed. At any rate, I went to the audiologist and had another pair made. I suspect this will also happen in 5-10 years with the IEMs I got last year. Just a cost of enjoying the benefits - like having to repaint the house every so often.