I know that you have stated that the version of bootloader isn't too important but I have 5 units with three different versions.
They range from version 1.6 to version 1.8 and I believe your current is 1.9.
Just for consistency, would it be possible for me to upgrade them all to the same version? I could not locate the bootloader "bin" for download.
73 de Perry - K4PWO