Phnx MT202pcs Speaker Phone gives Error in playback & record

[tlm]

The Phnx MT202pcs Speaker Phone gives Error while opening sound device when chosen for both playback & record in Audacity 2.1.0 on both a MacBook Pro 12,1 (Early 2015) and a Mac Pro 4,1 (Early 2009), each running El Capitan. By contrast, if other sound devices (such as built in or HD Pro Webcam C920) are used, there is no problem.

[kozikowski]

Apple (upper left desktop) > System Preferences > Sound > Input (or output). Does the speakerphone show up there?

Audacity gets its devices from the operating system and computer. If they can't see it, that's the end of the story.

Koz

[tlm]

Yes, the speaker phone shows up both in the input and output lists of the sound section of the preferences, in each case it is Phnx MT202pcs. It also shows up within Audacity itself within both the recording device and playback device dropdown menus.

[Gale Andrews]

Yes, the speaker phone shows up both in the input and output lists of the sound section of the preferences, in each case it is Phnx MT202pcs. It also shows up within Audacity itself within both the recording device and playback device dropdown menus.

If you still receive "Error opening sound device" you could go into /Applications/Utilities/Audio MIDI Setup, make the device the default input and output device, and for both input and output, set the sample rate to be the same as the Audacity project rate (bottom left of Audacity).

The rate of the Audacity tracks might need to be the same as the project rate too.

The web page for the device says it is full duplex, meaning that it is supposed to be able to play and record at the same time.


Gale

[kozikowski]

The instructions tell me this is a cousin of a videoconferencing system I've used in the past, however, the conferencing system and the sound system were a married couple, so we didn't have to do much adjusting, and they did work just fine.

We did publish a piece on this error.

http://manual.audacityteam.org/man/faq_ ... und_device

I know you can get into trouble with as simple an error as the stereo/mono is set wrong in the recording drop-down. Some systems don't care, some do.

Write back how you made out. I don't think anybody has posted with one of these before. And yes, they are full duplex, built for real-time videoconferences.

Koz

[tlm]

The attached screenshot shows the error after trying the posted suggestions. Nothing worked, unfortunately. Note in the screenshot that

1) The Phnx MT202pcs speaker phone is already set as the default for input / output
2) Audacity is set at the same project rate (32000) as in the Midi set up (it also happened when the project rate was 44100)
3) The error occurs when trying to play the audio (it also happens when trying to record)

Thanks for your help. I'm doing this troubleshooting using the Mac Pro I mentioned above since that's my goal. Since the error also occurred with the MacBook Pro I assume the same would happen there.

[kozikowski]

Did the instructions give you any clue at all what the settings should be? Google? Once you get into wacky settings like that, it pays to get real info instead of hunt-n-peck.

Koz

[tlm]

I'm sorry but I really don't know all that much about this device. My understanding is that it was simply purchased and then we plugged in the USB to the computer and it has worked great ever since. So, if the settings are "wacky settings", I'm not aware why or how to change them. Perhaps you mean that the 32000Hz number within the Midi Settings is strange. If so, I have no idea how to change it. That field is not editable in Midi (even though it looks like an editable text box). The user manual (available here: http://www.phnxaudio.com/resources-file ... Manual.pdf) says "Performance Speech processing and echo suppression at 32KHz sampling rate)" but that didn't help me understand this problem any better.

Thanks again for your help. If you don't know how to fix this particular problem, perhaps you could guide me in finding out who could help. Thanks for that.

[kozikowski]

I can think of one oddity that Audacity may not know how to handle. This is a full-duplex device, completely happy with pushing sound both directions on the USB cable at the "same time." (Same time in quotes. USB can't actually do that.) Even though the Mac can manage that, I'm betting Audacity can't.

On a guess now, Audacity steps on the record data at the exact time the Duet reverses direction. Or worse, Audacity tries to record during the switch. Audacity would see the wrong device.

Audacity doesn't like working with network drives for similar reasons. It doesn't understand data collisions and delays.

Koz

[Gale Andrews]

Have you installed the “Phoenix Audio Setup Utility” referred to in the manual?

Did this ever work with Audacity? Can you try 2.1.3-alpha from the top of http://www.audacity.homerow.net/index.php?dir=mac?

What applications have you successfully used to record with it, for example GarageBand? Does it record its own microphone OK (your side of a call)?

Have you asked on their support channel http://www.phnxaudio.com/help/ ?



Gale