In the list of activities in the Garmin Connect Android App, every pool swim activity uploaded from either my Garmin Swim or 920XT shows a distance of 2,500m. When I select an activity to get the details, then I get the correct distance. Currently using Garmin Connect 2.7 on a Nexus 4 with Android 4.4.4. The web interface is fine.
(Moved from Garmin Connect forum)