Mine is a solid 32x out of my harbor. If you don't want your sonar people to drop your TC to 1x every few seconds, do this:
Put your radioman and sonarmen in the stern quarters until you're out to sea. Sitting at their stations, they're merely doing their jobs by keeping the captain informed of nearby traffic.
Secondly, as soon as you leave the berth, dive to periscope depth for your trip out to sea, and you should be able to hold 32x.
Once clear of the harbor, and out to sea, increase speed to what you want, put your sonar and radio people back at their stations, and you're good to go, so to speak.
