I'm wondering if what you're seeing isn't just male retic behavior when they are in breeding mode. A few of my males make a kind of noise but it's not the constant wheezing you'd get with an RI, they're quiet and then will suddenly open their mouths and exhale very loudly. My SD male is particularly obnoxious about it. The sound is definitely not a hiss and was rather disconcerting the first few times I observed it.
I found that getting my males out for more exercise time helped stop the pushing.