Something changed with Your service?
When I log-in into my rigs remotly I don't see any differences in speed. They are all hashing with same speed when I look. It would deep only if there is problem with a pool (downtime). Very often I receive email from leaserig that my rig can't be managed or similar but when I log on the computer, it's still doing fine and there was no restart nor anything...Check for instance now. I've not touch anything and deeps in speed have finished. It's nothing on hardware side, it's more on the pool selection.

p.s. anyway, I've added 30min to his lease time