IP Phone speech delay & echo

[cpux10]

Hello,
I'm experiencing a problem on a TSW SP2 system:

An IP extension calls an outside line (for example my cell phone) using analog (TL11) trunks.
My cell phone starts to ring, but in the first 3-4 seconds of ringing, the TRAFFIC STATE of the trunk used (seen in SUSIP) is still OTGCAL, and it takes 3-4 seconds for the TRAFFIC STATE to turn into SPEECH.
Obviously, if I answer my cell phone during this period, I hear nothing.

After this period of time, I have speech connection, BUT the IP extension user hears his voice echo for a few seconds and after that, everything is normal. (I have echo cancellation on using PARNUM=108, and I think this is the time it takes for the echo to be cancelled.)

Any ideas on how to fix the first problem? and to reduce the time for echo cancellation in the second part?

 

[parnum]

go to TSW SP3, and latest IPLU and phone firmware. you may be trying to fix something that is fixed in these versions, there are many IPT fixes.

best parnum

 

[IPuser]

Taking a few seconds to 'converge' is typical of Analogue lines with pooer Echo Return Loss. They've worked fine for tears, but can be challenging for the Echo Cancellers.

First Approach is ensure the best impedance is selected , to match the analogue lines.
2nd approach is to reduce the transmission levels slightly on the Analogue card eg. try Short Line instead of Long.

Before all that though, should ensure all your transmission paramaters are set correctly for the Market and Type of line.

They could have worked fine for years as they are, but it matters more now you've gone oIP.