Frequency 2 Bar Graph

Trying to activate the bar graph option in Frequency 2. In the “Global Settings” menu I check the “Bar Graph” checkbox and you can see the bars very small and lowest at the bottom of the display but no matter what I’ve done (I must be missing something simple) I cannot get the bars to indicate any frequencies at all. All help appreciated.

Well duh. The bar graph cannot be viewed without audio pumping through the plug in. Nevermind.