toggle quoted messageShow quoted text
Total beginner here but I want to help get this going.
I have a USB 2.0 headset (2 different models/brands) I can try along with a few generic USB sound cards. I also have a powered 2.0 hub I got last night.
Want to share info off list?
On Sat, Jan 19, 2013 at 4:20 AM, Kristoff Bonne <kristoff@...>
As has been discussed and published a number of times on the net, there
seams to be a pretty serious problem with USB on the RPi, which has its
effects on using an USB audio-dongle on it.
From what I have found, it seams to be related to using a USB 1.1
device on the (USB 2.0) HUB of the Pi.
This has been my experience sofar:
- When I just plug in a USB audiofob on the RPi, I seams to be loseing
audio-frames during audio-capturing. The number of frames dropped per
second does differ quite a lot per device. On some devices (like a USB
headset), I only have 17 to 18 audio-frames of 40 ms per second (instead
- One trick seams to be to boot the Pi with the option set to limit the
USB speed to USB 1.1).
However, this seams to have a number of issues:
- in some cases, USB does not work anymore. E.g. my USB keyboard does
not work anymore.
- I had rapports of people where there are problems with the video
- When I use this trick and have 2 audio-devices active (both running at
48 Kbps full-duplex) at the same time, I have problems that the devices
says it does not have sufficient bandwidth for both sessions.
I find this a bit odd as USB 1.1 is -as far as I know- 12 Mbps and even
if you take the worse-case senario (2 * full-duplex stereo, 48 Khz
sampling, 16 bits/sample), I only have 3 Mbps / second
I use my RPi for developing the the c2_gmsk modem (codec2-based GMSK
modem for VHF and UHF), so I do need two audio-connections (one for the
headset for the user and one for the GMSK modem connection to the radio).
What is the experience of people on this group about this?
- is there somebody who has a revision 2.0 version of the RPi. Does it
also have this USB issue?
- Has somebody ever tried this with a USB 2.0 audio-device? As far as I
read, the problem with the USB-bus is related to using a USB 1.1 device
on the USB 2.0 bus. So does using a USB 2.0 device help?
Kristoff - ON1ARF