No sound in Bootcamp Windows 8.1

have you tried to navigate to the realtek audio driver and run that driver install for windows again manually ?

if you don't have the bootcamp drivers anymore then you can download them as a zip from apples site

please give up, better install windows8. EFI on MBP too old or diver not adapted.

i mean that it's impossible to make original sound work on windows 8.1.Downgrade is wiser.Otherwise, you need a USB sound card that plugged in to make sound work.

if you need windows 8.1 for anything but gaming or pro 3d then you can always install it in a virtual machine then you need not worry about supported drivers and timemachine will backup your windows too which it will not do with bootcamp

Im having the same issue.

I kinda think this is ********, because I too have run the bootcamp drivers from my USB drive and downloaded drivers from the Realtek website, and still nothing.

This is super ******* aggravating, considering it took me forever to just get 8.1 on my MBP.

I am having the same annoying issue on my early 2011 macbook pro. I ran the bootcamp and realtek drivers, I even ran the cirrus drivers. I went to my cloned image of my windows 7 bootcamp install and tried to swap the driver files by hand and that did nothing except fixed a screen brightness issue. After installing windows 8.1 twice I have had no luck. Thanks Mr.Cook.

I was thinking about upgrading my entry level MBP 13" late 2011 to the top of the line rMBP 15 late 2013 for gaming, I thought I could install Windows and run any game just fine without losing the OS X experience. I had no issues before with Bootcamp with Windows 8 x64 back when I had Lion. Now I'll just buy a Razer Blade and ditch Apple.

Sadly, once I installed 8.1 x64 on my current MBP with Mavericks, I've had every single possible issue with a laptop that according to Apple supports Windows 8.1, first I couldn't create an install usb drive without first burning the .iso file to a DVD, which was possible before Mavericks. I don't have a DVD with Windows 8.1, since I received the OS through dreamspark, so I come to think, what if I buy the rMBP that lacks a DVD drive? I found a way to get the option to create the install drive from a .iso file, attempted to install, then had an issue with the partition created by Bootcamp, Windows wouldn't let me install in that partition, nor I could erease it then use it with the tools of the install setup. So I went to disk utility, deleted the partition, and left that as free space, booted back to the setup, and finally installed Windows by creating an NTFS partition at the free space. After I installed Windows, and installed the drivers provided by Apple, I had no sound, the driver was not working, and spent 3 days actively looking for a solution online, tried a lot, none work. Finally uninstalled Windows 8.1, I'm using VM Ware now, but gaming is not the same on a virtual machine.

I thought Bootcamp had real support, this is not the case. Razer Blade, here I come!

I am having the exact same issue that you described! This is just utterly RIDICULOUS and DISGUSTING! And NO SUPPORT, NO UPDATES, NO HELP from anyone! Yes, I'm very p1ssed, I'm having this issue for almost a year now! I cannot install Windows 8.1 through bootcamp because the installer recognizes the hybrid MBR that bootcamp created and forbids proceeding. If I get rid of the hybrid MBR and try to install it natively, then Windows setup works perfectly, but the sound does not work at all as you described, no luck with ANY driver. I'm stuck. No, don't tell me to use Parallels or VMware! I tried those! I need real native windows for my work! Do something about it already! I bought this Macbook from Apple because I thought they are quality products with excellent support. Clearly I was wrong! I am extremely disappointed! I have a MacBookPro8,1 (13-inch, Earchly 2011).

Tell me which driver you installed, 'any' driver doesn't tell me much at all.

And if you want to yell at Apple that's up to you, but don't do it here, we're just volunteers giving our time to try and help you.

More information about the drivers that I also tried as the rest of they guys here:

No Audio Boot Camp Windows 8

I tried Bootcamp audio drivers from Bootcamp 5.0.5033, 5.1.5621, 5.1.5640.

I also tried to install Realtek and Cirrus logic drivers that I could find manually, also with the ones in the other thread.

Anyhow, not me or anybody could make this work as it seems.

Sorry for the 'yelling' its just the sound of complete hopelessness and it is against the ignorance for this problem, it is not meant for you.

5.1.5621 is the correct set for your Mac, try again with that, uninstall all previous driver sets.