The fact that its happening with other liquids and RDAs really does point to vaper's tongue. Is this Space Pirate stuff particularly potent? Its possible that's overloading your tastebuds. Maybe lay off that stuff for a few days.
Mammoth do you get full flavour from food and drink? If so I find it odd that you can't taste any juice at all.
I do know the last time I had a serious case of vaper's tongue the only thing that cured it was some dodgy far eastern juice, purposefully picked a flavour I hated, was chemical as hell but it was so bad I started to taste all the nice stuff again after a couple of hours.
To begin with I thought maybe it was just the Magma. I got one this week and at times it tends to evaporate flavour when running very hot. But the fact you say it happens with other RDAs rules that out.