DLLHost.exe crashing on EV Recalls

Solution is a multinode EV implementation archiving off to a S3 cloud

When doing recalls we are seeing multiple crashes of the dllhost.exe process which calls tha amazon plugin dll which handles the s3 connection

Faulting application name: DllHost.exe, version: 6.3.9600.17415, time stamp: 0x54504134
Faulting module name: AmazonPlugin.dll, version: 12.3.1.1082, time stamp: 0x5b07f2a0
Exception code: 0xc0000005
Fault offset: 0x0000000000014a8d
Faulting process id: 0x1f14
Faulting application start time: 0x01d469a54050309a
Faulting application path: C:\Windows\system32\DllHost.exe
Faulting module path: D:\Enterprise Vault\OST\x64\AmazonPlugin.dll
Report Id: 80179157-d598-11e8-80d7-487b6bd9b2f1
Faulting package full name:
Faulting package-relative application ID:

S3 is fine , no errors in logs. Images on s3 have been checked etc.

Changed buffer settings in EV which made things better but didnt resolve the issue

Ideas ?