dell r720xd fan speed control via racadm

I am playing around with the fan control via racadm, and I have this unexpected problem: no matter what I do racadm won't let me change the fan speed to 2 or 3. I can do 0, 1, 255. I don't understand why. I am on idrac 7.

/admin1-> racadm get system.thermalsettings
[Key=system.Embedded.1#ThermalSettings.1]
AirExhaustTemp=70
FanSpeedOffset=Off
ThermalProfile=Default Thermal Profile Settings
ThirdPartyPCIFanResponse=Enabled

/admin1-> racadm help system.thermalsettings.FanSpeedOffset
FanSpeedOffset            -- Selection for Fan Speed Offset(Platform Dependent)
Usage                     -- 0-Low Fan Speed, 1-High Fan Speed,2-Medium Fan Speed,3-Max Fan Speed,255-Off
Required License          -- RACADM
Dependency                -- NA

/admin1-> racadm set system.thermalsettings.FanSpeedOffset 0
[Key=system.Embedded.1#ThermalSettings.1]
Object value modified successfully
/admin1-> racadm set system.thermalsettings.FanSpeedOffset 1
[Key=system.Embedded.1#ThermalSettings.1]
Object value modified successfully
/admin1-> racadm set system.thermalsettings.FanSpeedOffset 2
ERROR: RAC0946: Failed to set the object value.
/admin1-> racadm set system.thermalsettings.FanSpeedOffset 3
ERROR: RAC0946: Failed to set the object value.
/admin1->