It's actually possible to completely remove the problem but it needs a fairly powerful machine (at least for 16km). Actually, prolly not that powerful by modern standards. Hmm... wait a sec...
Edit:
Well it runs at 10fps or less on my machine, but maybe yours will fare better...
http://www.subsim.com/radioroom/showthread.php?t=151558
Edit:
If you want an 8km version, I should think it'd be easiest to just ask Dan to send you his.