For anyone who has the original box with hard drive, and has upgraded.. plus @Lisa_CC
The original hard drives are Toshiba 1TB HDD's they are wearing and slowing the boxes down.
Before the upgrade to 360 I had already removed the original and replaced with an SSD which kept the box running smoothly. (I had an engineer visit and they confirmed that was okay to do).
The 360 upgrade, doesn't see the SSD. It does see the original HDD.
The original is dragging the operation of the box down. I have the pixelated issue on most channels too.
Removing HDD solves the issue - But.. you then have no TV guide and no options to record anything.
Only question now is, what SSD can be used in place of the Toshiba HDD that was originally supplied.
This would save lots of money and issues in the interim before the cloud service and fibre is fully operational.
It is also a really simple operation to switch the drives over, if needed you could send all customers a section of the box that needs one part removing and the other slotting in the same place, it would be user friendly with instructions to complete.
From an IT Engineer - Who used to specialise in testing Hard Drives :)