UI24 computer out level 10db too hot from Macbook pro
I have just bought the UI24 and have it connected via USB to my Macbook pro (early 2015). Now I'm trying to route the main stereo outputs of the mac into the UI24. I went to the "Patching" page and assigned USB-DAW 1 & 2 outputs to the Line in L & R mixer channels. The signal coming from the mac is too hot for the mixer's input stage though when outputting what should be 0dB. I'm testing by playing music from the Mac Spotify client with volume set full and the main audio output level set full. I would expect this to be true line level but the UI24 input is constantly clipping and there's no gain fader on the input - it's missing. So it would appear that the only way I can ensure no clipping is by adjusting the Mac audio output level down by what would appear to be around 10dB but I have no way of accurately metering that output level on the mac! What am I doing wrong?
thanks in advance