Thank you :-)
Do you have sound enabled? Actually it's "3D-Sound", just follow the ringing ;-)
(Hint: you can "open" some furniture/drawer/cupboards)
or addition: If you really can't find it (because actually should be pretty obvious as soon as you found the spot), then maybe you touched it accidentally and it did flow somewhere behind or so. Tried to avoid that as good as possible, but time was just bit too short to completely finetune all colliders^^
In this case you maybe should restart the app.