I've been reading about the volume issues with the DT50 212. Too loud, etc. Before I say anything else its the real deal amp. I'm blown away with the HD500 integration. The Solo models are to die for!!!!
Here's what I do to deal with volume issues:
Each amps output can be set to the expression pedal without using DSP. Watch for how to do this. I've taken my amps/tones and used this technique to lower the overall volume (around a maximum value of 50-60) while keeping the master volume on the high power position (pushed in). Keep the master at about 12 o'clock (or what you like) and use the output settings to level each amp (patch) to each other and to lessen the output. This can be done with dual tones as well, just set both amps to similar parameters, and same expression pedal.
Do you lose sound? At 50-60 ... no on most amp models. Some amp models lose slightly, but low volume is merely, usually practice.
Is this the perfect fix? Probably not. However, your amp/patches will be leveled, properly loud, and get full use of channel volume and master volume mixes.
When playing live a quick touch on the master can work wonders.
Let me know how this works out if you try it. His advice (see link above) for wah pedals is spot on too.
If its too loud ... move! LOL Happy jamming!