either some nods are messing the network, or the haspower is not propperly distributed and the network is abused with some pool having too much hashpower so blocks found by others are orphaned mostly...
edit: based on the pool stats here: http://jackpotcoin.miningpoolhub.com/index.php?page=statistics&action=pool
the pool has 2GHs which is around 70% of the network which has 2.9GHs: http://explorer.jackpotcoin.info/stats/
so there is probably the reason why others gets too many of orphans...
that pool is basically running the network itself which is sad and ruining the coin.
If anyone is mining on that pool, please move your hashing power!