As a side note, I'm using 5.x beta drivers on C-1500 (only single card setup) as they work better on low signal quality, 4.x drivers were terrible on low signal. Then again, on another setup, Technotrend S2-3200 with two nebula DVB-T cards, beta drivers can't tune HD-channels at all and generally miss half of the channels where 4.x get them all but signal quality bars are always on top (on 5.x they showed more reasonable values).Having configuration with Technotrend C-1500 and Anysee C-30+ i must say that partly zapping problems seemed to be related to Tehcnotrend BDA drivers. Zapping on Tehcnotrend and between those two cards were merely impossible until I took tehcnotren BDA drivers version 4.x back in use again.
Zapping worked somehow better after that and there was no such hanging anymore. Only starting TV section is somhow slow but will come eventually.
So what I'm saying here is that testing correct drivers for you own setup is more than recommended, I bet there are same issues with other brand BDA-drivers too.