I'm not sure what the trigger is for this but it seems to occur after a couple hours of not using Connect. So sometimes when I view posts in a community, the vote count for it is around half of the actual count when I go back to viewing the community page. If I open the community in my browser, the current vote count indicates the community view in Connect is up to date. I can view other posts or go back into affected posts and the count will be incorrect.
I think viewing other subscribed communities will also not fix the problem. It is corrected when I view one of my feeds and then go back to the posts. I've only noticed this happening with the Canada community on Lemmy.ca, so it may be community specific but I suspect it's not and my other subscribed communities aren't as active to test.
I've only noticed this recently, so maybe it's only been introduced in to last couple of updates, or it's been longer and I haven't paid attention.