It’s possible that Viki is uploaded better HQ video’s for those series which makes them out of sync. Viki mostly uploads a LQ first because it’s uploaded faster so volunteers can work on it as soon as possible and they add HQ later and resync it.
It’s happening on The Suspicious Housemaid as well. The Chief Editor of the team for the Suspicious Housemaid , upon noticing the off-synch issues will report this immediately to one of the viki moderators. Sometimes, the viewers themselves will contact the moderators to inform them. So if this happens, please contact the viki moderators right away, either brittany or stephanie and let them know about it. The viki engineers will work on it right away.