DAC expansion board output level?

Hello!

I have a Up2Stream Pro V3 with DAC extension board and notice that, if I have the volume turned up all the way in the app, I do get some distortion. When I turn the volume down one notch, it seems ok.

I suspect that it is exceeding the 3Vrms that my preamp is looking for on its input.

I have not tried the onboard DAC/output.

I personally would prefer a set output level (no volume control) if using the DAC extension board, with the level set at 3Vrms, like most audio sources. Having volume adjustment on a device affecting the RCA outputs just doesn’t make sense to me…

Is there a specification listed somewhere (that I can’t find) that lists the output level of this system with the DAC board?

Thx!