Device value switches between 10 and 26 when set to 10

[MParnaby]

Hello!

If I set a device value (brightness) to 10 in the Alexa app, the value then switches between 10 and 26 in the app. It's pretty obvious that the max value is 255 (not 100) so all values set in the app are multiplied by 2.55 at some point. After about 40 this behavior stops, I assume because the value returned is 102 and out of the range of the 0-100 slider in the app.

I can't fix this myself. I've tried modifying the brightness value in _onTCPControl (casting the value divided by 2.55 to an int) without success. I can, with some messing about in the code, get the value to switch between 10 and 4 in the app. That's not what I want either. It seems that sometimes the percentage value is sent to the app from fauxmo and sometimes the absolute (0-255) value is sent to the app.

I can perhaps fix this, but I feel like there's something obvious that I'm missing. Anyway, any help gratefully received! If I can fix this myself I'll put a PR in.

Screenshots to illustrate the issue.