We have to delete the Multiroom app every single time we use it and reinstall. Once we've used it once, it can't be used again - it says there is no WiFi connection. But if we delete and reinstall it works (but only once). It's happening on two different iPhones and three different iPads, so it's not the device. The speakers are connected to the the Samsung separate WiFi hub which is wired into the main router. Anyone got any solutions? Thanks.