inedible Posted February 7, 2008 Share Posted February 7, 2008 Hey all, My laptop has a digital volume control wheel on its side (like a regular volume knob on a discman for instance, except digital. (there's no min or max, it just spins))... which is dectected and understood by leopard... EXCEPT that when I stop turning it, leopard doesn't catch on, and just keeps lowering or raising the volume on its own. So, to reiterate, if I turn the wheel once, to turn up my volume a single notch, it works... though it continues to work for several minutes afterwards, turning my volume up to max, then beeping at me that I can't turn it up any further. Anyone know what's going on here? I think the wheel is using some kind of ps2 passthrough and is sending some sort of keystroke to change the volume, since it doesn't show anywhere in windows' device manager, and if I start using the trackpad and tapping keys frantically (both are ps2 devices), it seems to stop. Has anyone had any similar problems or knows any sort of solution for this? The knob is right where I normally grab my laptop to pick it up, and gets bumped easily on a regular basis. At the very least, does anyone know how to turn it off? I'm going crazy here! Thanks! Link to comment Share on other sites More sharing options...
inedible Posted February 10, 2008 Author Share Posted February 10, 2008 Shameless bump. Link to comment Share on other sites More sharing options...
inedible Posted February 21, 2008 Author Share Posted February 21, 2008 Sorry to keep bumping this, but I've been reading up on ps2 devices and I'm wondering if this makes any sense: So something like 8 million times a second the ps2 controller sends out a request to the mouse and keyboard to see if anything has changed... if the keyboard says "hey this guy pressed the A key" the signal gets sent back that yes, we have data, here's the scancode.. but in doing so, it takes a whole millionth of a second to say that, so the other 7 times the controller asks for data, the keyboard's still saying "A"... so to compensate for this they do something called debouncing, which like waits, and ignores the A until the keyboard says its ready again. So... I've guessed all along that this volume control knob is a kind of ps2 device, and it gets stuck on saying "volume up" or "volume down" until I frantically mash my keyboard... So... my question is, is there something like some kind of setting in the ApplePS2Controller.kext (or similar) to set the debounce rate higher so my volume control knob can tell osx it's done fiddling with the volume now? I've played with all sorts of keyboard repeat rate settings, to no effect. Anyone? Link to comment Share on other sites More sharing options...
mister_doodi Posted February 21, 2008 Share Posted February 21, 2008 Heres another theory, Macs don't have a feature quite like it so OSX is winging it as best as it can. You can still change the volume with the taskbar right? Link to comment Share on other sites More sharing options...
inedible Posted February 22, 2008 Author Share Posted February 22, 2008 Heres another theory, Macs don't have a feature quite like it so OSX is winging it as best as it can. You can still change the volume with the taskbar right? yes, I can still change the volume the regular way, though it's very annoying that if you accidentally touch the left side of the laptop it starts going BEEP BEEP BEEP BEEP BEEP as loud as it can, and when it's doing this you can't turn it down, mute it, or stop it in any way. I've left it to do its thing before and it stayed like that for over an hour of constant beeping, as loud as it can. So, while you'd think it's a minor little thing ("oh well, just change it in the taskbar"), it's a huge problem that makes the entire operating system unusable. Link to comment Share on other sites More sharing options...
Blurn Posted May 20, 2008 Share Posted May 20, 2008 Heres another theory, Macs don't have a feature quite like it so OSX is winging it as best as it can. You can still change the volume with the taskbar right? I have the problem too. And trust me it is quite annoying and frustrating. You can definitely use the task bar. What about when someone is using my laptop and they want to turn up!? Well, then I have to turn it off because it just keeps doing it. So I'm pretty sure he was wondering not for convenience's sake, but for the usability of his computer. And I agree Mac is doing pretty good with handling what it has, but it would be awesome to get it to work or disable it. So another bump. Por favor! We can fix this! Especially if it has something to do with PS2! Link to comment Share on other sites More sharing options...
antst Posted October 14, 2008 Share Posted October 14, 2008 Here is the solution. Replace ApplePS2Keyboard.kext with attached one. Don't sure that I did fix in the best way, but at least it works This is kext which is based on sources of original ApplePS2Keyboard.kext, with minor modifications to prevent this kind of misbehavior of Volume-Up and Volume-Down keys (our knob is volume keys). Guys, did you find any audio driver for U300/U305 which keep sound after wake from sleep? ApplePS2Keyboard.kext.zip Link to comment Share on other sites More sharing options...
inedible Posted February 21, 2009 Author Share Posted February 21, 2009 Thank you so much, antst! That completely solves my problem! When I found my debian install doing the same thing I was able to search linux forums for the solution.. It turns out that the volume knob on the u300 sends a keyDown signal, but never sends a keyUp to signify the button has been released... OSX thinks that you're holding the button down continuously. Link to comment Share on other sites More sharing options...
uketernity Posted January 24, 2010 Share Posted January 24, 2010 Hey Guys, Im having exactly the same problem in snow leopard but this kext doesnt fix it Any ideas? Oli Link to comment Share on other sites More sharing options...
Jonas_S Posted May 4, 2010 Share Posted May 4, 2010 Same ... any ideas on a snow leopard solution? Link to comment Share on other sites More sharing options...
guilherme berghauser Posted June 8, 2010 Share Posted June 8, 2010 snow leopard don't work !! help-me Link to comment Share on other sites More sharing options...
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