Originally Posted by tightrope
My D1 powers on or off just fine using my Harmony One. Are you sure you mapped the Dune Toggle On/Off to your Harmony? The Dune has discrete On and Off commands, make sure you use the Toggle. Good luck.
Well... if I may disagree... I would suggest the opposite. I mean, if you use activities in your Harmony, make sure your Dune has the discrete power on and power off commands correctly setup, then check your activity to make sure it will try to power on and off the Dune when entering or leaving that activity, respectively.
Using the power toggle is not wrong, but it may get out of sync if someone uses a different remote to power it on/off, or the front panel buttons, or if there's a power outage, etc.. The remote never knows if a particular device is on or off, it just assumes it is off until you choose an activity that uses that device, and sends the power on/toggle command when you enter the activity. If for any reason the device is already on, and the remote sends a power on command, it will stay on, but if it sends a power toggle, the device will turn off.
In your case, I would start by checking the power on/off commands. If you press "Devices", and choose the Dune, do you see the power on/off commands in the list? If you do, try them from there (if you don't, add them to the list using their software). If they are not working, you need to review your device setup. If they do work properly, you need to review your activity setup.