From my experience with remote and remote codes I can tell you that remotes often repeat a command even though the button was pushed only once. This would be why Timrhu could get a smaller movement of the VC by waving it by the sensor as the button is pushed. In that manner He is hitting the infra red sensor with less of the repeated commands to increase/decrease the volume. Some remotes repeat the command less if you are very careful to push the button down as briefly as possible.
A possible solution would be to add a universal type of remote that can be programmed with less "repeats" per button push. Some can be set programmed to do zero or one repeat of the command. The only caveat is that not all infra red receivers will respond to zero or one repeat which is why the number of repeats is adjustable to begin with. Also this type of remote can only be programmed by an authorized dealer/installer.
The RTI brand has the adjustable repeats in the programming software but I believe others do as well.
A possible solution would be to add a universal type of remote that can be programmed with less "repeats" per button push. Some can be set programmed to do zero or one repeat of the command. The only caveat is that not all infra red receivers will respond to zero or one repeat which is why the number of repeats is adjustable to begin with. Also this type of remote can only be programmed by an authorized dealer/installer.
The RTI brand has the adjustable repeats in the programming software but I believe others do as well.