How can you avoid unnecessary noise?

You answered correctly. To avoid unnecessary noise, it is important to maintain the vehicle properly. Replacing worn sideboard hinges or fastenings prevents parts from rattling or vibrating, which reduces noise. Additionally, correct stowing of cargo or properly using chains ensures that items do not move and cause noise while driving. Increasing tyre pressure significantly, however, is not a recommended way to reduce noise and can negatively affect safety and comfort. Therefore, focusing on maintenance and proper cargo securing is the right approach according to German traffic rules.