Yeelight Color bulb V1 bindings

Running Openhabian 2.3.0-1, have installed Yeelight Binding (2.4.0??)
Running a V1 version of the bulb (I assume, as it has the “chrome” base), auto detected.
Have added the following to default.items:

Switch Light_Bedroom_JohnSwitch "Johns Bedlamp" <Light> { channel="yeelight:wonder:0x00000000036dc2fb:color"  }
Dimmer Light_Bedroom_JohnDIM "Johns Bedlamp Dimmer" { channel="yeelight:wonder:0x00000000036dc2fb:brightness"  }
Color Light_Bedroom_JohnCol "Johns Bedlamp Colour" { channel="yeelight:wonder:0x00000000036dc2fb:color"  }
Dimmer Light_Bedroom_JohnColDim "Johns Bedlamp Colour Dimmer" { channel="yeelight:wonder:0x00000000036dc2fb:color_Temperature" }

and to default sitemap:

Switch item=Light_Bedroom_JohnSwitch label="Johns Bedlamp"
Slider item=Light_Bedroom_JohnDim label="Johns Bedlamp Dimmer"
Colorpicker item=Light_Bedroom_JohnCol label="Johns Bedlamp Colour"
Slider item=Light_Bedroom_JohnColDim label="Johns Bedlamp Colour Dim"

Issue is that the only thing that works almost reliably is the switch. When I logged into the paperui once and went to control, everything worked perfectly for about 30 seconds, and then it all went haywire again - touching color or saturation, just seemed to turn off the lamp, and couldn’t get it to work again… On the Android phone, the switch again seems to work, and the color picker mostly works, but dimmers etc don’t…
Have I missed something (probably), and how do I fix it?
Thanks.