I have so far been using a system with one master zone with a bunch of 2.5 mm jack Y cables to play in "party mode", where all zones in the house should play the same music at the same time. Syncronizing doesn't work because I have different types of sound card and a mix of SPDIF and analogue output, and it seems to be impossible to have them 100 % at sync. Since most of the zones overlap the difference is driving everybody crazy.
So is there another way to play to all zones at the same time or even setting up a zone which covers all the sounds cards I have installed in the computer? There are at the moment 13 zones in the house, but three of them are in the cellar, so I can run syncronizing between the media server in the attic (my large technical room) and the main server that stands in and plays to the cellar (in my small technical room) since there is no overlap between the first floor and the cellar.
The Y cable way works, but it's very messy. So I would like to have a way of getting rid of a bunch of adapters and cables, if possible.