There is a possible other issue, check to see how your Fault Policy is set. File/Project Properties, and look at the bottom of the box. If this is set to any other setting other than "Mute all on any node or XDAB failure", then pops and clicks would be expected on a project that has XDAB. We have been asked why there are other selections, if they can cause problems? Because with some projects that don't have an XDAB, the project may be better served with a more relaxed policy.
For example, lets say that there are four single NioNodes in four amp rooms throughout a theme park. Background music is transported via CobraNet from a single source NioNode in the main Control Room, as well as normal control of the system. They want to control the entire system using a single project (a Kiosk Mode page), but one of the problems that they have from time to time is the fiber for the network that goes out to the park will get cut. One to 2 NioNodes will now be isolated from the main project, both for control and CobraNet. So by setting the Fault Policy to "Mute only XDAB nodes on XDAB failure", the Nions will continue to run. A short, simple selection of background music is stored as WAVs in the NioNodes, with the play and stop button triggered by the CobraNet link LED. I understand that they will upgrade their Compact Flash from the 256 megs to the new 2 gig Flash sometime this next year, which will enable a larger WAV for BGM.
If this is not the problem, and you continue to have problems, get in contact with us, and we will take a look at your project.
Make it intuitive, never leave them guessing.