[Thinlinc-technical] Praise, and questions ...

[Peter Astrand]

Hi, follow up on the sound questions:

> 5) Sound recording: with a Plantronics headset with 3.5mm plugs I can
> record for example my counting of numbers from 1 to 20 on the server,
> but often one or two of the mostly latter few numbers would be echoed -
> this is unusable with dictation software in a VBox WinXP machine on the
> server. The problem is not the connection on the server to the XP
> machine: a native Linux audacity recording on the server would already
> have the echoing. Seems to be some transmission issue between client and
> server. With a Sennheiser USB headset this does not happen - only I had
> to jump through loops and find out how to set the recording volume on
> the command line of the IGEL as its alsamixer did not adjust the volume
> far enough up. Perhaps all of this is an IGEL issue though (UD5-LX720,
> latest firmware)?

It is unfortunately quite common that the volume on various terminals is 
incorrect, especially for recording. If the USB headset works correctly, 
I'd say that this looks like an issue with the IGEL sound card driver. Do 
you get any warnings or errors in the IGEL log files? You can for example 
check "dmesg" output, if you have access to a terminal.


> 6) Sound playback currently is stuttering at about 3Hz, not sure why
> this is. Some clipping issue? This had not been the case before I
> started trying out the Sennheiser headset. But then again I just upped
> the recording volume, not playback, and playback through the monitor's
> speakers also stutters.

We haven't heard of such a problem before. As you perhaps know, the client 
side PulseAudio daemon was upgraded in ThinLinc Client 4.0.0. If you want, 
you can try an older client, and see if the problem is present there as 
well.


> 7) Could there be a way perhaps in the future to make pulseaudio use the
> headset for recording and the external speakers for playback? I guess
> some extra negotiation between pulse on the server and in the client
> pulseaudio plus a setting button would be necessary for this to happen.

Our client does not have such a setting at this point. However, if the 
client system has a local PulseAudio server (for example if you are 
running our client on a Linux workstation), it should be possible to 
configure this with the PulseAudio GUIs.


> 8) Pulseaudio: For some time I had to manually start the pulseaudio
> daemon for the user on the server to have any sound at all. For reasons
> I do not understand currently this is not necessary any more. I have
> bi-directional sound via pulse, but then there is the stuttering now.

A pulseaudio daemon on the server side is not necessary. Applications 
connects to the client side daemon over the SSH tunnel.

If you find out that a server side daemon is required, you may have 
stumbled on some application bug. Which application requires this?


Rgds, 
---
Peter Astrand		ThinLinc Chief Developer
Cendio AB		http://cendio.com
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