Hi Mark,
There have been a lot of changes to the "plumbing" for the menus in mojoPortal since 2.3.6.1. Are you able to upgrade your site to the latest version (2.3.6.4) and see if the problem persists?
Does this happen on every module on the site or just select ones? If not on every module, is it only on those that use a ModuleWrapper?
Thanks,
Joe D.