Alright... Not a big deal, but figured I'd post it anyways...
1) Loop Switch On
2) Loop Region Length Size smaller than the size of a loop/clip you want to preview
3) Rewire to Melodyne (3.1.0.9)
4) Play Song
5) Preview a Loop/Clip, you'll see the preview time counter go black and glitch for a short period of time and then continue.
This is on Macbook Pro... up to date as of today, running Live 5.2 and Melodyne 3.1.0.9 rewired into Live. It isn't a huge issue or anything, and goes away when turning Melodyne off. Not sure if this happens with Reason as well or other hosts/clients.
Greg