Grand Central Disconnecting after upload

Hi There

I was wondering if someone could give me any advice as sending me a little crazy

I have a grand central M4 and can sometimes upload to it and it works fine however roughly every third time i upload to it crashes the board and I then need unplug and sometimes double click to reset, I've tried different leads, and different machine i.e. a MacBook with a USBC hub breakout and a old Mac Tower using USB2 and everything crashes the same

This is a example of the error i get

Device : ATSAMD51x20
Version : v1.1 [Arduino:XYZ] Dec 30 2018 21:24:00
Address : 0x0
Pages : 2048
Page Size : 512 bytes
Total Size : 1024KB
Planes : 1
Lock Regions : 32
Locked : none
Security : false
BOD : false
BOR : true
Write 16664 bytes to flash (33 pages)
0% (0/33 pages)write(addr=0x20004034,size=0x1000)
writeWord(addr=0x41004014,value=0x4000)
readByte(addr=0x41004012)=0x11
readByte(addr=0x41004013)=0xd
writeWord(addr=0x41004004,value=0xa501)
readByte(addr=0x41004012)=0x11
readByte(addr=0x41004013)=0xd
readByte(addr=0x41004010)=0x1
readByte(addr=0x41004011)=0
writeBuffer(scr_addr=0x20004034, dst_addr=0x4000, size=0x1000)
[======= ] 24% (8/33 pages)
SAM-BA operation failed
write(addr=0x20004034,size=0x1000)
An error occurred while uploading the sketch

If anyone can help I would very much appreciate it

Cheers

James