[LAD] Multi-Channel channel order

Is there any existing 'standard' for the order of channels for higher-than-stereo multi-channel streams? I'd assume this would be defined for interleaving or something, though that's not what it's needed for: I think the port groups extension should specify an order for all the channels of the various types of group. Though this isn't necessary useful in the normal case (ports are separate ala LADSPA), with this replication stuff and presumably other things the host and plugin are going to have to deal with sets of buffers, and having a predefined standard order for them seems like it would make life a lot simpler and faster (and not having one seems to have no benefit). For example, for discrete non-interleaved 5.1 (using a full channel for the .1) we have 6 channels: left, center, right, rear left, rear right, LFE (see http://lv2plug.in/ns/dev/port-groups#FivePointOneGroup) What order should these be passed in? Any existing practices? Thanks, -dr