In Norm and Warm modes, Release controls the length of time it takes for the compressor to be fully deactivated after the input signal drops below the threshold level. If the release time is too short, distortion can occur on low-frequency signals.
Set this control to 0 for the fastest release time, or to 10 for the slowest release time. Depending on the program material and the parameters used, this represents an approximate range of 15 ms to 1 second for Norm mode (or the primary release of Warm mode).