Asstastic Smelling HRM - HALP

There's no other way to say this....my heart rate monitor smells like *kitten*. Like, really REALLY bad. I've washed it and dried it, put it in baking soda, used shampoo/Dawn/everything I can think of, and as soon as I put it on and sweat even a little bit, it reactivates the stench. Is there SOMETHING I can do (ANYTHING) to get rid of the smell? I don't want to put it in the sun because I'm afraid of ruining the electronics. Same with harsh chemicals. Thanks.