I have just purchased the Innuos Zen mini Mk3 (firmware 1.4.5) and have it setup as a Roon core sending the digital stream over USB to my Mytek Brooklyn DAC+. Every time I standby the Brooklyn unit and switch it on again the Zen somehow immediately triggers the Brooklyn (via the USB) to reset its volume attenuation setting to zero (it also causes the sampling display to flip to 384kHz and 24 bit which is not in itself an issue, but may be related). If I don’t manually lower the volume after switch on, it will immediately play at full volume as the Brooklyn is feeding my power amplifier directly. This is clearly hazardous as it means potentially damaging speakers if a stream is started without first lowering the volume before playing anything. My previous Roon core was using a Microsoft Surface book via USB which did not exhibit this behaviour. I am currently working around this by using a preamp with it own volume control between the DAC and power amp.
I have the Brooklyn configured for ‘Device volume’ in order to use the slider in the client interface when playing music. If I switch to Fixed volume or DSP the problem disappears but I lose the client volume slider.
Has anybody else encountered this issue or can offer advice? Of course i may be missing something.
The issue does seem to be simply a compatibility issue between the Innuos Zen mini and the Brooklyn when linked using USB for the digital feed to the DAC+. There may be configuration settings that are causing the effect but I haven’t tracked them down yet. The Zen which is setup as my Roon core and connected via ethernet to my router is in all other respects working very well. The Brooklyn is currently outputting via a Quad 99/909 pre-power combination to Dynaudio Contour 30 speakers.
Ok, problem resolved! Innuos support modified the Zen Linux OS USB initialisation code over remote connection session so that volume is set low when the connected Brooklyn is powered up. Maybe a workaround but it is working well. Great support!