Honestly, after about an hour of searching, I cannot find an easy answer for Home Premium. There are answers for using the group policy editor in the other editions...
Suggest looking into DISM. To find out more about DISM (which has a remove-driver feature) run an Elevated Command Prompt and type in "dism /?" (without quotes).
Also, see Add or Remove a driver from a Wim Image using DISM
Another option is to find the .sys file(s) associated with the Realtek driver (use driver sweeper to find their names through Realtek - Sound) and go into C:\Windows\System32\drivers and rename all of the Realtek sound driver found .sys files to .bak (instead of .sys). You will also need to disable windows updates from finding the files online. To do so:
1. Click Start Menu
2. Click Control Panel
3. Click System and Security
4. Click System
5. Click Advanced System Settings
6. Respond appropriately to any UAC popups
7. Click the Hardware Tab
8. Click Device Installation Settings
9. Set yours as mine is in my attached screenshot.
Did you have any luck with stopping your driver from automatically installing?
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