Production issues at two of the largest U.S. liquefied natural gas export terminals threaten to reduce shipments just as an energy crisis hits Europe and Asia, where buyers are desperately trying to rebuild depleted inventories ahead of winter. Freeport LNG is experiencing a wax buildup in its pipelines due to impurities in the gas it receives, said people with direct knowledge who asked not to be identified. As a result, LNG shipments from the Texas export terminal will be reduced for the remainder of October through November, the people said. Freeport officials declined to comment. ... Meanwhile, a production unit...