1.03 bug???

[swimsalot]

Been running 1.03 since it came out, noticed a problem recently.
In my last 2 MP dives, I was unable to get a sonar contact on the enemy sub/subs.
Last one was less than 8nm from me; I looked above/below the layer (500 feet), nothing.
Mud bottom, sea state 3.
No seamounts in the way.
Checked both TA and Sphere, BB and NB.
UUV didn't get it either.
Couldn't figure out why my torp was tracking something, but I couldn't hear anything on that bearing.
Received TIW from an area with nothing there.
On replay, with "show truth" on, there were no enemy subs on the map!
But, as the dive progressed, I could see the UUV's, torps, and CM's they had launched (3 sub FFA).

So, what could cause an invisible sub?
Not running any mods, clean install.
Maps were from Seawolves and GNSF; other players could detect me just fine.

System specs:
AMD 3500
2GB Crucial RAM, 3200
Gygabyte K8N-Pro Mobo
Radeon 9800 Pro
Dual 80gb Western Digital HD in RAID Zero
Windows XP
Broadband cable, router, firewalls off, prot open.

Ideas anyone? Jamie?