problem with I2S DAC and simple equalizer

I am using volumio 2.513. First installed my I2S DAC: HiFiBerry DAC PLUS, everything was working correctly, volume mixer set to Hardware.
I then installed and enabled simple equalizer and it worked a little, I could change the equalizer settings. After I restarted the system the first thing I see is that the volume bar/circle is greyed out, and when I go to Playback options the Output device is set to: HiFiBerry DAC Plus trough equalizer plugin (which seems to be the case) but the volume mixer is set to: None.

Is this a bug? How to solve it?