Strange problem, need help.

[Zero Niner]

I've come across something weird. I can't get the engines started at the start of a patrol. I've posted at the Sh4 forum, cross posting here in the hope someone could help.

http://www.subsim.com/radioroom/showthread.php?t=140811

I just started my 5th patrol (2nd in current sub) electing to start outside the harbour. However I cannot move . Whatever speed I order, I get the message "cannot comply".

This is a Gato-class boat. I had no problems during the previous patrol.

The only thing that changed was what I did in port - upgrade conning tower to the one with the AA gun in front, swapped some crew, added deck gun and AA guns because the conning tower gave me the default guns (3" & single 20 mm, I upgraded to 4" and twin 20's x 2).

No mods installed in the interim.

I have no idea what could be causing this. Any ideas?