I often do live sound reinforcement for events at our church services. We have lately been using Behringer 212D speakers. During an event today I found that if I turned the main output volume down suddenly a loud hiss and hum were introduced, and if I turned it down further the speakers turned off completely!
Both of these problems completely went away when I turned the volume back up over a certain threshold.
Looking into this I found that the 212D speakers have an "undervolt circuit protection" feature that will turn off the amplifier when the input voltage is too low. This seems to be what we were running into. However, I am running a line out from an EQ (after the mixer) and it seems strange that I would run into this. I do split this line using a fully stereo (balanced) phono cable (all three connectors are balanced and all cables and all equipment are balanced).
So, is it maybe that the splitter is cutting the voltage in half? Or maybe somehow the speakers being connected to the same line is confusing the circuitry? Or am I way off base here?
Thank you for your help.