Hi Emma,
Thanks for contacting us – though I’m sorry to hear you’ve hit up against this issue.
So far as I’m aware no other users have reported this and it’s not something we’re seeing many reports of. Am I correct in thinking the loading symbol (and the page fade in as a whole) is something supplied by your theme (‘Salient’)?
theeventscalendar.com/knowledgebase/testing-for-conflicts
If so, have you been able to ascertain if things work as expected with a default theme such as Twenty Seventeen. While I understand you may have a strong and reasonable desire to use your chosen theme, isolating if it is in fact the source of the issue is a worthwhile first step (since the problem could of course have its roots elsewhere).
Let me know what you discover!