Did you ever figure this out? I am having the same issue with the same PPC. Are you running a custom ROM? I am using WinMo 6.5 as well, Simplicity version 5.2.28244 (11/12/10), Manila version 2.5.20191912.0 with Radio 4.49.25.95. I have tried this on a fresh install as well, with and without CHT. I also ran this on Athine ROM for about a month but it was the same. What are your system specs? Did you find any answers or work arounds? Oh, I am using the beta Waze 2.1.99.114. I am very curious as to your input
===
I have tried several things e.g. turning off onscreen alerts from other programs like outlook, that cuts it down a LOT.
I have adjusted the A2DP bitpool settings to see if it was the BT causing the problem, I even went as far as to disable BT.
What seems to be happening now is that the screen freezes, not the PPC just the app. you might be driving along and suddenly you stop getting prompts and you stop moving on the map and the screen does not respond. If you press the power button quickly to turn the screen off, and then press it again to turn it back on sometimes that gets it to start working again. Sometimes you have to pres the window key or the back arrow to go down to a home screen, and then press the Waze icon again. Waze just refreshes and realises that "Hey you need me?" and is OK again. I can get away with that about three times before I have to reboot the PPC. What I have found is that is that if ignore the directions given to me several times it does some kind of a funny dance where it does not know where it is and reroutes like 15 times in a minute and then freezes. A couple of times it just cuts out back to a home screen.
I just adjusted the File system Cache settings for the system and the filter, if it seems to have an affect I am going to have Clean Ram monitor system ram and try to recover memory holes. I ride the bike allot from February to December so it may take a while for me to obtain and answer that I am confident in. I am putting a Ram Mount on the bike once I have the carbs back in so it may be sooner that either of us think

looking forward to input and replies.