You need to make sure you use correct settings for the coin. Displayed hashrate is ofcourse changing if you make the job easier for the graphics card.
Dont do things backwards. Use easy settings -> See that it works! -> Then take one card from your rig and try to make it work faster -> Once you succeed, make all graphic cards use optimal settings.
Thats what I have learned from rushing things in the past. You end up 7 days from now with no coins because the blockchain will not accept wrong hashes in the end. Coins need 520 confirmations in order to make sure noone can get coins easier than anybody else. Thats what a fair distribution is all about.
My thoughts from understanding cuda is that we need new mining software to make use of new graphics cards in order to press through the 50Hs/s (and accepted) boundaries. Maybe someone has coded a private miner for himself and thats why hashrate increased. We need a new cgminer/ccminer and fast

Cachecoin has pretty good things ahead but there are so many good alternatives with optimized miners available we should look for a miningdeveloper to look into this. Maybe Vega is good for this coin with fast 8gb memory. Any ideas?