I wrote a response in
this thread which has some relevance.
More fitting towards this question directly though, are you pointing your contacts (e.g. facing them dead on at relative bearing 000?) The wider profile you expose to active sonar, the easier you are to detect.
Also, make sure you're not in the "duct". Sound travels further in the duct rather than being below the layer. This makes periscope-sighted attacks harder.
Beyond that, how do you set up your attack approaches? Are you broadsides, on the nose, etc.