No, for us users there is nowhere a possibility to change the name of mixers. But UC Surface/Control always identifies the machines by their IP-adress, so technically nothing gets "mixed". I can imagine that using static IP-addresses instead of dynamic addresses has an effect on how the three mixers line up. Another idea could be to start the mixers in a certain order (wait long enough until it has booted and UC has identified the mixer). If this does not work you could add a number to the names in the channel strips, f.e. 1_Kick for kick drum on first RM...
