[quote name='roman_sub' timestamp='1434033225' post='2796140']
FromFrFr
It sounds like it could be an issue regarding relative pitching. Good singing is largely a mental process (no doubt, some will disagree...), and if you've heard yourself back through the monitors to be able to pitch correctly initially, you should be able to retain the memory of the relative pitch.... If, on the other hand, you could not "align" yourself to start with (i.e. you were not sure where the note you were singing "should" be pitched), then it sounds plausible that you will be off-key when you can finally hear yourself, having not previously established a link between your vocal pitching and the other instruments. I guess just to add to that, securely knowing where the pitches without simple reference is hard and may take years of practice!!
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This sounds like a possibility. Don't forget that while you're singing, you're listening to the other band members, playing yourself etc.
So there's some multi - tasking going on, while you're attempting to do what so many have told you not to. Some singing lessons may help ?
Best wishes for solving this