User talk:BillWharrie/OSX and USB input devices

The following is copied (and edited as appropriate) from the original page on the manual wiki.

Gale: 03 Dec 10 FWIW even in 1.3.12 it's still quite common for people to write to feedback@ and say they have selected their USB/firewire input device in preferences, Audacity recognises it but records silence. Selecting it in Audio MIDI Setup apparently fixes it (not sure if changing the sample rate is the real thing that fixes it). Almost any Logitech USB device seems to create this behaviour in Audacity. Where exactly in the Manual is this page going? I thought we had agreed material like this would be on the Wiki?

Bill 03Dec10: Yes, it should probably be in the wiki. But on the wiki, doesn't it conflict with the other Mac USB information? And isn't the wiki supposed to also support 1.2.x? I find the wiki Mac information confusing with the main text referring to 1.2.x but "sidebars" or parenthetical comments referring to the "latest beta" or "1.3.x". I created this mostly to point to from the forum for Mac users with this problem, after taking a user exactly through this procedure.

Gale 04Dec10: I don't know whether it conflicts with the Wiki, but yes Wiki has to support 1.2 and 1.3 until 2.0, after which the disparity will be removed/ toned down. What better way do you suggest of referring to both versions on the same page? In my first comment I meant that users have selected Logitech in Mac system preferences (as well as in Audacity Preferences), some even say they can see the sound in System preferences but they record nothing in Audacity and see no meaningful activity on Meter Toolbar until they go to Audio MIDI Setup. Do you never hear of this on the Forum? To me it's near pointless to use System preferences since Audio MIDI (far from "extra credit") is always the tool that will make recording work if anything does. Against that, you can see audio input in System preferences, but so you can in Audacity Meter Toolbar? What about hearing the audio? I presume the "output slider" in System prefs doesn't let you hear the input? Am I missing some other benefit of System Prefs? When I've got your further views we'll see about where your page might fit on the Wiki. PS shouldn't this page refer more generally to USB interfaces and Firewire devices as well? Bill 04Dec10: Thanks, Gale, for taking the time to comment on this. I don't recall any help I've given on the forum where setting up the USB device through System prefs didn't work, and I then had to send them to Audio Midi Setup (AMS). "Extra Credit" (I was being a bit glib) is now gone from the wiki page, and comments about Logictech devices and the need to use Audio Midi Setup is highlighted. The ability to see that your USB device is actually communicating with the Mac (sending audio) is a major benefit of System prefs that you don't get in AMS. System prefs is much easier to use. I don't like that "Mac Bugs" page on the wiki, and take issue with the statement "it's necessary to set up external sound devices (such as USB and Firewire interfaces and USB microphones or headsets) in Apple Audio MIDI Setup" as this is obviously not true - System Prefs works 99.9% of the time (100% of the time in my experience). AMS is useful you want to change the bit depth or sample rate, and I'll add that to the wiki. Quitting Audacity and restarting is only necessary, in my experience, when plugging in a new USB device, so I'll add that to the wiki as well. I'll PM Koz and Bruno on the forum and get their comments on the wiki page. Gale 05Dec10: Yes if you already have the external device running when you launch Audacity then you can I think tweak away in AMS. Undoubtedly some of the people from feedback@ who can't get Audacity to record the input selected in Mac sound prefs will be on 1.2 - they often don't give the Audacity version. But cases in 1.3.12 are reported. We'll have to see how your page goes. I'd prefer not to have it as a "personal opinion" but to adjust Mac Bugs to suit, assuming your content is too long to fit into Mac Bugs. The strength of "necessary to use AMS" in Mac Bugs stems 1) from my not knowing for some time that Mac had system prefs 2) from it actually being absolutely necessary in 1.2 to use AMS to have any hope of an interface working with Audacity. 1.3 is clearly better here as a general rule. As your page is now, I believe it is leaning too much to USB turntables and RIAA adaptors etc. and not enough to multi-channel interfaces and the like where (certainly on Windows) you *must* match sample rates or the devices won't record or will give distortion/overdub drift etc. Bill 05Dec10: I have no experience with Firewire or multi-channel devices, so can't give advice on those. I originally thought of this as an expansion / complement to USB_turntables, or for those using simple USB interfaces such as the Behringer UCA/UFO-202. I think another page for multi-channel interfaces would be more appropriate, and could hopefully be written by someone who has some experience there. Once that is in place, perhaps the Mac Bugs page could link to both, pointing to this page for simple 2-channel USB devices, and to the other page for multi-channel devices. I put this page in my "user space" so we could tweak it before putting it in the "real" wiki space. It could simply be renamed, or copied and pasted to a new page, once everyone is satisfied with the content.

Gale 11Dec10: My feeling would be that Mac Bugs is more appropriate as a general link to point Mac users to (covering the whole gamut of external devices). I'm not confident that the general advice there should be to use system preferences because I know it wouldn't work in all cases. I think we could work the image of System Preferences into it for its diagnostic value. Since USB turntables must still support 1.2 I don't think we should move there either to saying that System Preferences is the preferred way to set up. I would suggest the best way to handle this is to move your page (if you think it is finished) to a new page USB turntables/Mac Tips which gives a framework for possible USB turntables pages for Windows or Linux too. I think this is OK given the intention is to keep USB turntables even after 2.0 because of its depth and (hopefully) up-to-date links. I'm not sure who could write a special Mac page for setting up multi-channel devices but as at least half its content would duplicate your USB input devices page, I suspect its main connection should be with Multichannel Recording. I also think that platform-agnostic help about selecting multi-channel inputs in Audacity might be more generally useful.

Bill 11Dec10: This page is more than a USB turntables page, and less than a multi-channel recording device page. As such I would not want to retitle it as a USB turntable page, nor would I want this page to be expanded to multi-channel input devices, despite possible duplication of content. This page is a step-by-step for any Mac user (with 10.4 or later and 1.3.12 or later) to get any USB input device connected to their computer and communicating with Audacity. It addresses the "greyed-out input slider" issue and the "missing input selector" issue in a logical and straightforward manner, something that Mac Bugs does not. And how is this a "bug", given the gyrations that Windows users have to go through? I stand by the advice of using System Prefs first since it will work in 9999 out of 10000 cases (at least - I have not encountered a Mac user on the forum who had to use Audio MIDI Setup). Take them through the simpler interface first. If it doesn't work, take them deeper. A user who has never touched AMS should still have the default settings of 44100 2ch-16bit. That is the only possible use for AMS - to change the format. An interesting exercise is to have AMS and System Prefs open side by side. Changes to the "Default Input" in AMS are immediately reflected in System Prefs Sound Input, and vice versa. Another interesting exercise is to select "Line In" in System Prefs and "USB Audio Codec" in Audacity Devices Prefs - Audacity successfully records from the USB device! The Mac Core Audio system is not as quirky and fragile as some seem to think it is. It is actually simple and straightforward. And it 'just works'. So the point of using System Prefs is that it is a foolproof way of determining (outside of Audacity) that your USB device (or any connection) is properly connected and working. The next time you get an enquiry about USB sound input on Mac, point them to this page. Then we'll have a better idea of how much use AMS really is.

Gale: 25Dec11: Sorry this has hung around; you should have prompted.

I agree that "no input level control of USB devices" is a hole on the Mac Bugs page that should be addressed (and to me and many Win > Mac converters, a hole/quirk in Mac behaviour). The title of Mac Bugs is unfortunate; it should have been called "Mac Issues".

I don't know why the Forum experience is different, but I usually see one or two Mac users a month on 1.3.12 + (feedback@ or my inbox) who set their FW interface to 96000 Hz or higher, and Audacity Project Rate to 96000 Hz or higher and recording channels to "8" or whatever. The Audacity response is "error opening sound device" until user goes into AMS. Plus some Logitech USB mics don't seem to respect Sound Preferences.

But as the most common case is USB turntables/cassette decks/2-channel interfaces I don't mind saying to try Sound Preferences first, as long as user really is on 1.3.12 + and not 1.2.

This page needs to be a separate page; we need to figure out how best to segue links to it into various other pages. I am not as sure as you that it should not be called "USB Turntables/Mac Tips" given the USB turntables page is actually the main page addressing set up of all basic USB devices, but am happy to go along with keeping the current name. I suggest though "USB input devices on OS X" to match with USB mic on Linux.

I think it's easiest to make the changes then adjust things after we can see it, rather than talk about it. Are you OK with me doing that, then you can review and tweak it?

Bill 26Dec11: Go ahead with your tweaks. The only reason I was working on this page recently was that I recently upgraded to Lion and notice how different AMS looked. A much cleaner interface, I think, separating the Audio and MIDI functions into separate windows.