Hey
I checked from the AudioFuse Detail page that the Output impedance is rated 33ohms. It might work for larger headphones but that sounds a pretty high number for 3,5mm jack as it is usually used with lower impedance phones. High output impedance will affect sound with low impedance phones and generally output impedance should be 1/8 of the headphones impedance.
I use in-ear-monitors which have low impedance so I would prefer 2ohm output like the RME Babyface Pro has in its 3,5mm. So if you're going to sort this out at some point you'll have a customer.
Cheers, J.
