Just heard from PSarkissian at Line 6 and it was a faulty interface box that fried my guitar.
I have no further comments or opinions
They have replaced the box and cables
Line 6 Support was most OUTSTANDING and I thank them here again.
The trouble is you have no way of knowing if you have a bad box until it's too late if you are doing upgrades
There doesn't seem to be any risk if used for Workbench
Signing out here...Chuckewheat