Update README.

README.md

@@ -331,7 +331,9 @@ Additionally, NOISE has an absolute value circuit.  Patch audio into ABS to get
 
 #### S&H
 
-A dual sample-and-hold and trigger-and-hold.  Sampling may be triggered by CV (on the rising edge of a trigger or gate) or button press.  If nothing is connected to an IN port, sampling for that channel is from an internal white noise source (range 0-10V).
+A dual sample-and-hold and trigger-and-hold.  Sampling may be triggered by CV (on the rising edge of a trigger or gate) or button press.
+
+If nothing is connected to an IN port, sampling for that channel is normaled to an internal white noise source with range 0-10V. Alternative options for the normal source noise type and range are available on the context (right-click) menu.  The normal source selection applies to both channels.
 
 Each channel can be toggled into track-and-hold mode.  In this mode, when the input at GATE is high, or the button is held, the input is copied to the output.  When the gate goes low, the input is sampled and held until the next gate.