You're right.
I started the unit yesterday with the compressor OFF-> silence
and switching the compressor to ON -> immediate sound ( despite the cold temperature )
The message 'tubes warming up' appeared at first starting up
Hey MJMP isn't this maybe the opposite of the compressor/wah issue ? if they are out of circuit it all works fine ? BTW Gregory, the ambient temperature change shouldn't be a big issue (not to say it isn't part of the problem, but I doubt it, I've run my MP2 inside , outside, back of a very cold semi trailer (needed heat lamp for my hands..)), however, let the tubes cool down (~10-15 mins) before you move it to help tube life.
So Gregory, I think what MJMP is asking, is when you turn on your MP2 (it will goto/default to the last used patch (whatever you had it set to when you turned it off last (no matter how many times you turn it off/on))) does
this patch have the compressor set "on" ? (coz that's how it will start up). Now the known MP2 issue as I understand it is that if the compressor is set to off (and wah off), it shouldn't be an issue ?? and if it's set to on it takes a bit of time to settle, But you are getting it to work by turning the compressor on