We have been using the unit for many years, but we only switch it on when needed. The dehumidifier has a sensor and measures the humidity. When we dry laundry, it automatically switches on the compressor. When it's humid in autumn and winter and the moisture pushes into the house, it switches on every now and then, even without laundry, and it never smells musty. The ventilation runs all the time, which makes sense, because air movement dries laundry or even walls much faster. You have to remember to empty the container, otherwise it switches off completely.
Just out of curiosity, I unplugged it while it was running. You have to wait a while because the compressor has to shut down completely. After plugging it in, the compressor started up again immediately. So it should also work with a timer.

If the power fails, the unit switches off and must be switched on again manually. It is therefore not suitable for operation on a timer.

It works for me: Plug out: unit off, plug in: Unit runs.