Classified causing BBpress permalinks not to work

Hi, I have the same problem with dutchmen as I saw in post https://premium.wpmudev.org/forums/topic/classified-causing-bbpress-permalinks-not-to-work-anymore?replies=14#post-327048

My installation:
WP Multisite 3.4.2
Buddypress 1.6.1 (3000 members)
BBpress 2.1.2 (400k posts)
Classifieds 2.3.0.6

My problem is occasionally:

1. when I activate Classifieds on Multisite the permalinks on BBpress dont work (page dont found) I save permalinks and everything works in about half an hour then again permalinks on BBpress dont work (page dont found).

2. when I activate Classifieds on single site the permalinks on BBpress work in about 3-4 hours then again permalinks on BBpress dont work (page dont found) so I have to save again the permalinks and work for 3-4 hours...

On both cases none submit a classified.
Also I havent change any settings in classifieds when activated.

Deactivating the Classifieds plugins an permalinks work perfect.