I don't remember if this behaviour of sh3 was already discussed:
When you are on periscope depth the hydrophone works and shows a line on F5 map to sound contact - and this is correct. But when you raise the periscope, the contact lines on F5 map from hydrophone dissapears
So if you wish to see sound contact on map you must lower the periscope... Is it a bug, or I don't understand something?