[atbukc]

Just for me to try to have a better figure of what may be happen, can you please tell me what broadcast method are you using?

// --------------------------------------------------------------------------------------
// Broadcasting Data to Wireless Display Units
// --------------------------------------------------------------------------------------
#define BROADCAST_DATA 0 // 0= Disables Data Broadcast, 1= Broadcast by WiFi, 2= Broadcast by RF

If you have WiFi coverage on the garden shield, preferably define the BROADCAST_DATA to 1

My setting is 
// --------------------------------------------------------------------------------------
//   Broadcasting Data to Wireless Display Units
// --------------------------------------------------------------------------------------
#define BROADCAST_DATA       2          //

I have wifi in the shed but it can be patchy sometimes so I would prefer to stick to RF, seems odd that all other fields receive data fine, just not the AQM fields, how often is the AQM data transmitted?
Maybe if I am at the limit of the RF range my WD keeps missing the AQM packets if they are only transmitted infrequently perhaps?