I’m only connecting a cable to the Left/Mono output jack, but only 1/2 the filters are sounding. If I connect jacks to both Left and Right I hear all filters. Why is the Left output not sending Mono when no cable is connected to the Right output?
After posting, I decided to clean the output jacks with contact cleaner. Problem solved. 
Wow, always good to be aware of that issue. Applies to all electronic gear really…
Stephen
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