From the Kpt.
What you describe is not a bug and will remain integral to GWX. In more detail:
I set the hydrophones to be extremely sensitive... once an enemy hears you he will charge to your last known location and depth charge it in all likelyhood. Not only that... but he will call his friends too. When he gets closer... Sonar/Asdic kicks in and he tightens his search pattern if he gets a return.
Now that being said... Even if the DD
LOSES CONTACT with you... he will still hunt for you and depth charge the vicinity for a very long time indeed... and if a new contact is made with you... that "hunt-time" clock starts all over again.
Furthermore, DD's communicate and operate in a coopreative fashion. One may maintain you as a contact and basically direct the other to DC you.
What you are describing as a bug... is an intended and intentionally modded feature.
Footnote: If a surface ship is travelling 15 knots or less, he is able to use his hydrophone... though they will slow down to cut down on their own noise factor.
Footnote #2: You
can escape the DD's.