Alvin explained that for some DAB radios, the design of the chips was not well thought and that could lead to some faulty behaviour.
We had a real life demonstration of it with Tom's radio, a DAB and FM radio that worked just fine for the FM side, but the DAB was working correctly at the beginning when cold, but had some hard time as the components were getting hot.. It turned out that the reason for the dysfunction was a power supply that was not right and slightly above the voltage needed for the DAB components to work well.
Another Radio that was brought at the skill share was an FM radio with a broken antenna. The antenna could not be fixed as we had no material to do so, but we had a good explanation from Alvin on the correlation between the length of the wave (with are very long for FM radio) and the length of the antenna. The antenna has to be long enough to resonate with the radio waves we are trying to capture.