Little to no maintenance is needed for rubber mulch.
When used for playgrounds, it may be necessary to rake the mulch occasionally under swings, slides, or anyplace little feet tend to dig in. Other than those areas, there is little to no maintenance required.
Rubber mulch can be cleaned just by hosing them off, or for deeper cleaning can be cleaned with a general purpose, non-acidic cleansing agent or mild dish soap and water.