After may years of problem-free usage my iOS app keeps showing all Devo M5's offline when they aren't. They are all working and have a green icon. If I click on a device I can see the connected items. 
 

i can't reboot from the app or look for new software while in this state because the app says it can't connect to the devices. 
 

Reboot fixes for a day or so then they show as all offline 

Don't know the hardware version.