After passive DI-boxes came a new generation of active DI-boxes. These came with high impedance inputs, that did not alter the sound as their passive counterparts did and also required external power. Usually, they used 48V phantom power coming from a mixing desk or an audio interface, that originally was used to power condenser microphones. Usually, these no longer came with transformers used in passive DI-boxes, as they were replaced by electronics, but that caused an old problem to rise once again – inability to lift ground without the aid of external power supplies or battery power. Batteries were unreliable as their current altered depending on the charge, and as they depleted, the quality of the sound degraded. Using an external power only added to cable clutter and added another possibility to create a ground loop.