Simulator not installing

I have a smartapp which I have been using for playing notifications on my Sonos musicplayer. It worked fine on the Simulator when I set it up a few weeks ago, but now when I try to install the Simulator it no longer lists any of my Sonos speakers, and I cannot complete the install.

It lists “virtual devices”, “sonos”, and “physical devices”, and there is one radio button on the same line as “sonos”.

I have these lines in my code (as usual):

	section {
		input "sonos", "capability.musicPlayer", title: "On this Speaker player", required: true

I get this error message (which I didn’t use to get):

grails.validation.ValidationException: Validation Error(s) occurred during save():

  • Field error in object ‘physicalgraph.device.Device’ on field ‘name’: rejected value [null]; codes [,,,,,,,,,,,,,,,,,,,nullable]; arguments [name,class physicalgraph.device.Device]; default message [{0} cannot be null]