Every studio owner should be aware, that synthesizer and effect equipment which can store its settings in memory usually have a small battery to keep that memory powered during being shut off. These batteries can last 5 or 10 years but then they fail to power the memories and the settings are lost. But even worse, after another while they can leak acid and destroy the circuitry, so an exchange should be done.
Here are some pictures showing the Block 4 studioequipment while changing the batteries to illustrate this rather easy operation and where to locate them on specific devices. However opening the devices can be dangerous, they can be destroyed by touching parts of it and emitting static electricity plus, and even worse, it can even give you deadly electroshocks by touching exposed parts of the power supply. So please be aware of this and take care. Under no circumstance Block 4 nor Malte Steiner can be hold responsible or liable for any cases of destroyed equipment or even damages or death caused by operations inspired by this website. In doubt its safer to let an experienced technician do the change.