Ok, I'm using the 800 series no winglets, flying from KMSY to KDTW and about half way there the radio stack locks up, I can't talk with ATC or input my NAV freq's. It will allow me to switch options in the ATC window (viewing the list of airports etc.) I usually fly the 700 series and have never had the issue, is it a known glitch with the 800? PS I've tried the same route 3 times and its happened all 3 timesregards,Paul LedfordN0418NWVA

Paul, Have you updated your PMDG 737-800/900 with the latest Service Update?Best,Vin ScimonePMDGwww.precisionmanuals.comhttp://www.precisionmanuals.com/images/forum/devteam.jpg

I'm not 100% sure, I know i've done the upgrade to 1.3 but i'm downloading the one released on 7/29 now and will try it again.Paul LedfordN0418NWVA

Hi Paul,You definitely need the new patch (7/29). Once applied should fix the problem.FYI: In the future, you can also try searching the forum. There have been several threads regarding this issue.Thx