Just doing the DB BR 155 scenario Steel Cycle on Ruhr Sieg Nord and every time I go into a tunnel, the sound drops out. On a couple of them, it's just suddenly dropped out, and I've been able to sound the horn after I've emerged from the other side and the sound comes back. On this, one of the longer tunnels, the sound seems to crackle and die out, and only changing the camera angle managed to bring it back after. There were no sounds at all playing in any of the tunnels and it happens in every one (and there are quite a few on RSN). Annoying not to have the SIFA alert sound!