Sometimes wheezing can be the result of a very small piece of stuck shed around the nose or mouth that can create a wheeze/whistle when breathing normally.

Do you see any signs of mucous or phlegm coming out of the snake's mouth? Any mucous spots on the cage walls? Any bubbling in the snake's mouth? Usually these symptoms are present during the course of an RI. What are your hot and cool side temps?

I wouldn't immediately raise temps, as anything over about 85 can potentially be fatal for a BRB