[Havan_IronOak]

I'm guessing that he bought the Steam Silent Hunter GOLD deal (that's what I did) It contains SH III, SH IV and SH 5.

The same problem happened to me just recently.
I encountered a sound contact that first appeared as a merchant contact. When I zoomed in the map mode a bit the grey trail somewhere to port quickly became two blue contacts to starboard.

Given that I was tired I decided to cheat and see if there was something worth pursuing (I was at zero torpedoes and headed back to Pearl) Plus the game was getting slow and I thought perhaps ending the mission would clear the issue.

When I activated the external camera and scanned way out, the ocean stopped appearing but in space I saw line after line of warships all destroyers. I saved the file and decided to investigate it later.

I'm running SH4 with the following mods

Generic Mod Enabler - v2.6.0.157
[C:\Program Files (x86)\Steam\SteamApps\common\Silent Hunters wolves of the pacific\MODS]

01 Improved Stock Environment_v3
02 ISE Realistic Colors
03 Dark Recognitionmanual
04 MaxOptics IV for SH4 1.5
05 OM_SH3_Command_Keys
08 3000 Meter Bearing Tool (1920x)
09 Sobers Better Sand II
10 Captain Midnights CBS News
12 BBC World
merchant skinpack release