I wrote a kext. I still have no sound, but I do have internal speakers, line out, etc... listed in my sound properties and it made a popping noise once on start up. It might also have something to do with the EFI string I added to my com.Apple.boot.plist too.

The whole kext comes from an ALC262 where I did the necessary tweaking in replacing all DevIDs with ones listed for ALC272.

I suspect the problem lies in the AppleHDA file in /Contents/MacOS. I hex edited it to replace all device ids with the ones for ALC272.

I get the following errors on start up:

Mar 23 13:43:12 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != result" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAPath.cpp" at line 1168 goto Exit
Mar 23 13:43:12 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != pathSet->getWidgetAmplifierGainRange ( &zeroValue, &minValue, &maxValue, &minDB, &maxDB, kPATH_CONTROL_SPATIAL_CHANNELID_Master )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 248 goto handler
Mar 23 13:43:12 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "false == pathSet->isAmplifierGainAdjustable ( kPATH_CONTROL_SPATIAL_CHANNELID_Master )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 3572 goto Exit
Mar 23 13:43:12 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != result" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 3527 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != result" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAPath.cpp" at line 1168 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != pathSet->getWidgetAmplifierGainRange ( &zeroValue, &minValue, &maxValue, &minDB, &maxDB, kPATH_CONTROL_SPATIAL_CHANNELID_Master )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 248 goto handler
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "false == pathSet->isAmplifierGainAdjustable ( kPATH_CONTROL_SPATIAL_CHANNELID_Master )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 3572 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != result" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 3527 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != result" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAPath.cpp" at line 1168 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != pathSet->getWidgetAmplifierGainRange ( &zeroValue, &minValue, &maxValue, &minDB, &maxDB, kPATH_CONTROL_SPATIAL_CHANNELID_Master )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 248 goto handler
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "false == pathSet->isAmplifierGainAdjustable ( kPATH_CONTROL_SPATIAL_CHANNELID_Master )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 3572 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != result" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAEngine.cpp" at line 3527 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != widget->setUnsolicited ( true )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDACodecGeneric.cpp" at line 830 goto handler
Mar 23 13:43:13: --- last message repeated 1 time ---
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "result" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAWidget.cpp" at line 2294 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 != widget->setConnectionSelectNodeID ( fSelectionsForEachWidget[inputWidgetIndex] )" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/AppleHDAPath.cpp" at line 694 goto Exit
Mar 23 13:43:13 James-Bolins-Hackbook-Pro kernel[0]: Sound assertion "0 == controlRange" failed in "/SourceCache/AppleHDA/AppleHDA-157.1.24/AppleHDA/DspFuncLib/Functions/DspFuncVolume.cpp" at line 512 goto Exit

I'm enclosing the kext, my linux dump, a pinconfig, some device info, and my com.Apple.boot.plist if anyone wants to tear it apart. I'm much too busy trying to get 10.5.6 installed on my newer Core i7 desktop to even want to mess with this.

I have a Toshiba Qosmio X305-Q701

Click to view attachment

After weeks of searching I FINALLY found a working kext for ALC272. I take no credit for creating this but I will be happy to share it with everyone in need! Feel free to PM me if you have any questions and enjoy your working sound!Click to view attachment

Who do we owe the credit of creating this kext?

Thanks for this. I now have sound output on my Dell Mini 10v, the only thing left now is the microphone. Has anyone had any luck with this?

this "AppleHDA_ALC_272" is not kext
,how can i use it ?

psychotropic

Thank you so much! I now have sound on my Dell Mini 10v!

Fantastic. Much respect!

Kind Regards

Hugh