I am running two separate networks at my home. One is a DSL network, to which OOMA is attached by Ethernet Cable. The other is a Cable Modem network to which computers and printers are attached. Both have wireless access for iPads/iPhones/Computers.
Everytime I print (Cable Modem network), OOMA goes into Registration Mode and ultimately sets Do Not Disturb mode to on. My OOMA Telo device is located right next to the printer (additionally, I have an OOMA Handset located in another room).
The DSL network is tied into a Linksys WRT300N Router.