What would be the cause of high ORPHAN BLOCKS
i am getting loads of them. like 70 to 80%
last 24 hours i minted 16 blocks but 12 of them ORPHAN

i mint 1 block, then after 2 or 3 confirmations block suddenly becomes an ORPHAN.
seems bit suspicious.
or mint 1 block and 5 active connections suddenly drops to 1 or 2 connections.
seems bit suspicious also.
All nodes coming from NOVA EXCHANGE.

Do you mean PoW or PoS block? In my wallet PoS blocks minted fine.
Try set internet time and then restart wallet.