[asterisk-users] Best strategy to find and solve voice quality problems

[Yves A.]

Hi,

in my company we use an asterisk installation with around 50 soft- and 
hardphones of all kind.
 From time 2 time the users (almost only Softphone users) report some 
voice qualities... mostly echoes.
These problems do not occur on all PCs at the same time and since setup 
of our PBX almost any PC user
has gotten these issues.
When I come there to check, everything is fine again... and I can´s see 
anymore, what could have caused
the problem... may it be a high network load, or a high cpu usage or 
whatever...
I activated call recording to "hear" the quality after such 
missing-quality reports but every call I listened
to showed no issues in the recording so I assume the problem is on the 
client side. Because it is not
always the same user or the same PC I think it cannot be a misbehaviour 
like wrong headset usage or
a problem of a single PC.

What is the best strategy to find and solve these kind of problems? Are 
there any (free would be cool) tools
that can monitor the pc-state (concerning at least network and cpu- / 
process usage) over a long period
and display the results in an appropriate way?

Is there a way under Windows XP / 7 to ensure Bandwidth for VoIP like 
QoS (google only showed me such
"settings" for Lync or Windows Server machines...?

Is there a way under Windows XP / 7 to ensure CPU-Bandwidth for 
Applications (like VoIP Clients)?

Thanks for any hint,
yves