If you are doing this on the broadband, try going to the narrow band and assigning the tracker. Then when you go to the BB, use tracker review (I think it will work from NB to BB) to select the contact, and mark it again. I know it might be a pain, but for whatever reason this is happening to you, this might be the only workaround.
I've also heard something about disabling the hardware cursor, but I don't know about this for sure.
I have a small bit of this sometimes, but nothing that causes a big problem with gameplay. The BB on the Western sonars can be a bit funny sometimes it usually works ok once you are more familiar with it.
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LW

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