Bluescreen from savonaccess.sys

Hello,

I have a client pc, that gets blue-screens in kind of random intervalls. It's a brand new PC and the Problem persists even after a new windows installation.

With "BlueScreenView" and "windbg" I kind of identified the problem to be the driver savonaccess.sys
This is a driver by Sophos.

BugCheck 3B, {c0000005, fffff88001b6ac0d, fffff880094918c0, 0}

*** WARNING: Unable to verify timestamp for savonaccess.sys
*** ERROR: Module load completed but symbols could not be loaded for savonaccess.sys
***** Kernel symbols are WRONG. Please fix symbols to do analysis.

So the question:
What is the next step for fixing the problem?

windbg log is in the attachements and a zip with various log files from "dm-log-collector" (several .txt files for debuging purpose like services, dxdiag, drivers,...) is available here if it helps: http://www.filedropper.com/computer-2903201516440321

regards and thanks for the help!

Edit:
I've tested the RAM with memtest86+ over the weekend (17 passes) with 0 errors

FYI: I got redirected to this Forum by the folks on http://www.sevenforums.com/bsod-help-support/365610-problem-identified-savonaccess-sys-how-fix.html