An audio ramp-up or ramp-down effect can be done using Logic and Control blocks.
Open the device design. The Component Library menu lists Logic and Control modules.
The following will be used in the example:
Logic to Control
Pink Noise Generator (audio input source)
Voltage Controlled Amp
When the Latch button is ON, the input is high (true). The Logic to Control will convert the signal to be tied into the Control Ramp,
The Control Ramp will set the Threshold (%), Up Rate (s), Down Rate (s), and the Ramp Type.
The Control Ramp then ties into a Voltage Controlled Amp (Ctrl node) and Control Meter. An audio source (Pink Noise generator) is tied into the Voltage Controlled Amp audio node. Lastly, an RMS Meter is used to monitor the output signal.
If the input signal is low-to-high, the Up Rate will take effect. If the input signal is high-to-low, the Down Rate will take effect.
In sound masking systems where you'd want to change the level of masking, you would create Presets in the Logic to Control converter for your desired control levels.