I also have 2 UE boomboxes. However, they cannot be operated simultaneously via Bluetooth from the same source (e.g. iPad). What is possible, however, is to connect a splitter cable to the source (e.g. a 3.5 mm jack splitter cable for the iPad) and then you have two outputs, each of which can be connected to a boom box (they also have a 3.5 mm jack input). This works without any problems.