Hi!
Hope you can help me w a small issue that has arisen at my studio
System :
Intel Quadcore on Asus mainboard / 8 GB RAM
2 x HDSP 9652 PCI
1 x ADI-8 DS
4 x ADI-8 PRO
All connected w ADAT Lightpipe

I have been running 1 x HDSP & 3 x ADI-8's for years, and have had absolutely no problems whatsoever - Quite on the contrary, I would say that if all products worked as well and integrated as seamlessly as RME's always do, the world would truly be a better place...!

However, I've just acquired further 2 x ADI-8's and aspire to expanding my system to 40 analog 24 Bit/44,1 KHz I/O.  I installed the new card (2) , updated the firmware and the drivers installed automatically from the already installed card (1) as usual...

I connected the 2 new ADI-8's to card 2 and the analog outputs to the line inputs of channels 25-40 on my analog mixing desk, and everything seemed to work just fine.  As used to as I am of RME's stuff always working at first attempt, I was obviously very happy but not at all surprised...

I opened a project in my DAW (Nuendo 4), and started working after rerouting as to utilize the additional 16 analog outputs. 

After approx 30 minutes the system started to slip out of sync, which resulted in clicking and stuttering of audio flow. 

Since this was an issue I had anticipated, I had my coaxial/BNC connectors ready at hand, which I proceeded to connect by daisy-chaining the 5 ADI-8 units together going out of unit 1's wordclock  and in to unit 2's wordclock and so forth, and terminating w my 75ohm terminator at unit 5's wordclock out. 

This seemed to work at first, but after another 25-30 minutes, the system starting slipping again...

There quite a few things I can think of that I could try towards fixing this problem, however I am in a tight timeframe here, and would appreciate if you could direct me through the process of making the above system configuration work...?  Your help will be much appreciated by everyone here...!

I should probably mention that the 2'nd HDSP 9652 is without the expansion board that provides the usual 3'rd pair of ADAT I/O and wordclock I/O.  I don't have the expansion board...  (Can one be purchased separately...?)

Thank you & all the best,

Adam / MMI