Hi.
I think I translated your text correctly. So, there is no bug actually. You need to collect 5 items and then talk to the person, who is labeled with the name. When you go towards the lamp post is emits the signal, because in story the weird frequency actually comes from it, so that's why when you go towards it you can here the signal. You should definitely look for 5 items. no bug in there. You can watch any videos and see which item you missed.
Best to you!