I'm not sure what chemicals you are using but I use Tetenal kits and they provide alternative processing times for developing at 30 C (86 F) that might be something to try. It might be easier to maintain a lower temperature and the longer development times are said to help even out the process. Here's a pretty good write-up with comparisons:

http://paulagortazar.blogspot.ca/p/t...it-review.html