I used the 900's briefly, last year on a tour. If things are still as they were then, it is most likely a volume limit difference between the monitor engineer's "cue system" and the muso's systems.
Lets say you change the volume limits from 4 to 8 in the receivers (belt-packs) after syncing, the transmitters still have the belt-pack volume limit setting at 4. When you sync a pack in cue mode it copies all the settings from the transmitter, including the belt-pack volume limit at 4. In normal mode your all good with your volume limit set at 8. When you go to cue mode volume limit is down to 4 for each of the synced systems.
To make sure your all good set all "RX Setup" settings in the "Utilities" menu on the transmitter before syncing to any belt-packs.
HTH,
Jim
Also, in case you didn't know, the "volume limit" reduces the maximum output level. It's not a traditional style limiter.
