I have found that an older version of Mix Station X Air Pro works better for me than later versions. (I've proved older versions of Mix Station X Air Pro Version 0.003.0 backed up July 9, 2018 from my old phone works with BDF2000 using Mackie Control protocol.)
Can I get a more recent version, but not current version, from December 2018 or January 2019? I wish I knew what the version number was, but I don't. I know version 1.0.3 & 1.0.5 are not compatible for me.
Mixer Model: XR18
App Version: 0.003.0 & 1.0.3 & 1.0.5