Finding the Invisible One

From: Detective
Description: We need to take a closer look at the Riverside Abode in order to figure out whether there are secret rooms or anything else in there. I'm sure the musician is hiding somewhere inside and is just pretending to be invisible. come, buddy, let's look around.
Completed: I didn't see anything suspicious, did you? Yes, a quiet backwater, a moored boat, the cherry garden covered with a snow cap, and this music... I just don't get it, where does it come from?