I've had my ProQ cold smoker for a few years now and it's something I use often, the smoke marks inside are testament to this. My love of this compact piece of kit was born from attending a Coldsmoking.co.uk course a few years ago.
They have kept their online shop and now stopped their physical courses in favour of building their Youtube platorm with instructional stuff. I was due to attendant a charcuterie day until you-know-what took it down and part of the day was talking about air-dried duck breast. They have now moved online and have a great Youtube channel and one thing that they have posted is how to do cured and smoked duck breast.
I'm actually not a fan of duck, outside of the crispy one you get in Chinese restuarants, but equally I recall trying a Venison version of this and liking it so caution to the wind I gave it a go. I double checked the information needed on the three part video and got going.