Why does Band GPS have issues locking in southern hemisphere?

[Windows Central Question]

I've had a lot of issues with getting the GPS to lock while traveling. No issues when traveling around the US, but once I hit the southern hemisphere - it either won't lock at all or only records a portion of my run. I've had this issue in Cairns, Australia (but not Sydney - it worked fine there); Argentina; and now Brazil. I sync the Band with my phone prior to running. Any suggestions?
Thank you