I don't think that should be happening. If you have a multimeter or amp meter measure the current the circuit is taking. Hot and fast charge loss likely indicates you have a short across the power supply somewhere. Op amps don't usually draw all that much current unless you they are driving a low impedance load and I don't think this one is so you are likely looking at a wiring error of some kind.
If it likes 15V best, then the Murata (although a bit pricey) is a good bet. A cheaper alternative would be 2 15V regulated wall warts (with the disadvantage of needing 2 power plugs)
Peter