If you’re sick and tired of unwanted noise in your signal chain, then you really should be thinking about upgrading your power supply. More often than not, hum or buzz is caused by power-line noise. Obviously, some of that noise can be from your amplifier - but you don't have to live with noise from your pedals, most of it can be removed!
Individual pedals, especially distortions and digital delays, are likely to have some kind of power-line filtering, but without an isolated power supply - that is, one where each output powers one pedal only, and the power lines do not cross - it's possible to pick up noise from other pedals sharing the same power source.
Another benefit of isolated outputs is knowing that the current delivered to a pedal will be consistent - particularly important with digital pedals. Isolated power units will send a specified amount of current to each output, ensuring that each pedal receives exactly what it needs. On the other hand, Daisy-chain, parallel, or non-isolated supplies divide the current produced between the outputs, meaning the current between pedals can be variable.
Learn more: Guitar effect pedal power supplies: what you need to know