I'm impressed with how useful these are for solving ground loop issues.

Details coming soon about a new amplifier build that required several different voltage outputs from a single PSU and had noise as a result of grounding issues.

In audio, ground loops can be cut by converting the electricity to magnetism and back, or light and back.

On the audio side, 1:1 transformers can be used to break a ground loop however these are not perfect and the signal quality reduces.

The other ways to cut the loop is at the PSU - either with separate PSUs or a by using one of the many isolated DC-DC convertors that exist.

They can step up or down too, or just provide the same input/output voltage. Though it can only output 100mA, the TBA1212 can be used for a preamp, or TBA1211 (gives 5V) can be used to power a bluetooth module.

With some additional filtering before/after the module, you can solve ground loop issues with these at the PSU side, which won't affect audio quality and won't cost lots of money either! They're really small too!