When dropping audio signals into Pseudo Devices, vsmStudio automatically fills the free cells following a left-to-right, then top-to-bottom principle. Means: if you have 4 Pseudo Devices, each with 4 audio signal slots, and you want to assign 16 audio signals, you can grab 16 audio signals from the signal list and drop them into the signal list, beginning with the first signal. vsmStudio will then drop the remaining signals automatically in the following way:

Pseudo
Video
Audio 1
Audio 2
Audio 3
Audio 4
AVideo_1Audio_1Audio_2Audio_3Audio_4
BVideo_2Audio_5Audio_6Audio_7Audio_8
CVideo_3Audio_9Audio_10Audio_11Audio_12
DVideo_4Audio_13Audio_14Audio_15Audio_16

This can be very helpful and time-saving, but it also may have an undesired effect, e.g. in case your audio signals do not allow for a sequential order or you want to skip specific columns. It sometimes may be helpful to let vsmStudio fill only the first column and leave the other ones untouched.

You can achieve this when working with Pseudo Device Groups. In doing so, you can filter the visible (and therefore assignable) groups while dragging and dropping signals. The following video shows the achievable results.