1. Subscribe and download the MOD from workshop.

2. Open your Steam directory then go to:

\steamapps\workshop\content\227300\1814887717

3. Copy actros_mp3.zip to your local MOD folder located in:

C:\Users\username\Documents\Euro Truck Simulator 2\mod

4. Activate actros_mp3 in MOD manager ingame. It should work just fine.