I think I may have found the "limits" of the IFI Diablo... I recently got a set of Monolith AMT headphones, which feature a 32Ω driver whose sensitivity is rated at 90 dB/mW at 1 kHz; these can take outputs as strong as 10W per channel (200 ms peak), so I thought: now I can really test the balanced Turbo mode of the Diablo. So, with the AMT headphones placed on a desk, I engaged the Turbo setting on the amp and started turning up the volume...everything was fine (and LOUD) until 1 PM, but as the volume knob reached around 2PM position, silence settled in abruptly and I had to go back to 11-12, or to switch to Normal mode, to resume normal operation. Is this a sort of "protection" thing?