Why are Radio 3 and Radio 4 quieter than other stations on DAB?
This is not a fault but a characteristic of the stations. Many stations process their signal before transmitting it, in order to boost quiet passages and give a louder overall sound. This reduces the contrast between loud and soft passages (the dynamic range). Radio 3 and Radio 4 do not process their signal, so, if you are listening in a quiet room, you can enjoy the full dynamic range of, for example, classical music. If you are in a noisy environment, most DAB radios have a Dynamic Range Control (DRC) feature that you can turn on to increase the overall loudness.
