sundance-communications.com/forum Forums TDM Business Telephone Systems NEC Telephones & Systems NEC SL1100 Playing Distorted MoH Music

Hello Yall,
We just uploaded a new audio file to an NEC SL1100. This was one audio file that had 6 paragraphs and background music between paragraphs, but both voice and music were formated as one audio file. The issue is that the voice portion plays crystal clear, but the music portion plays with obvious distrorion. We reformatted the audio file at a lower volume, we changed the music style to soft music with no use. The audio plays great on the MoH unit and on other phone systems we tested with, but not on the NEC SL1100. Again, the voice portion is clear, but the music portion is distorted.

I would really appreciate any tips

Thank you

I haven't come across this sort of thing before. Normally the whole file works or doesn't. Have you tried just making a file with the music only and playing that one back and see what it sounds like??

Not sure if anyone else in the US has had this problem..

Thanks Paul, I have not tried music only, but I will. This has really been very strange. I agree with you, The whole audio should be one way or the other, not 50/50!!

Is the entire file in the proper format?

Yes it is, the music is in the same exact format as the voice portion. The voice is crystal clear, but the music is distorted...as when you crank up the volume through some bad speakers!

Music and speech use different paths of frequency. that said, have you investigated the paths that feed the SL1100?

What kind of pathway is feeding the SL1100 ? Pots, VOIP, etc ?
How are you monitoring the music output of the KSU ?

Have you tried using BGM feature of the system and what were the results there as far as quality of the music ?

Did not ask if format the same. Is it what the the Manf tells you to use???

Sorry, The required audio file format by the MoH device attached to the phone system's MoH port is of the following format:

MP3, 128Kbps, 44.1KHZ, Mono

The voice and music portions of the audio file were steched together as a single audio file in this format.

Sorry for the delay TJ. I am still waiting for the phone system's vendor to reply back with the answers to your questions

OK, I thought you said you uploaded a file to the phone unit, not an external device.

I apologize, I should've been more specific. the unit we use is an IP based unit (gets its updates by connecting to our MoH server via the Internet). This client has similar issues before they became our client. The unit we are using currently is our latest and most commonly used units...I never experienced anything like this before...It is either all good, or all bad. Do you think separtaing the audio file into separate voice cuts and inject BGM music between paragraphs as separtae files would help?
I also acted on the suggestion of creating a music only file and waiting for the unit to pick it up. I will report the outcome at that time.

Than

Would a bad PRI cause this issue? How do I prove it?

Yes, if the PRI is being delivered via some form of VOIP. The sampling/compression rate of IP causes this, even on cell phones. Ask the service provider if they are using IP as the transport medium and I think that you'll find your answer there.

Thanks a lot ED. by saying the "Service Providor" are you referring to the phone company that provided the PRI? I know the MoH unit is an IP based unit, but it does not stream alive audio, it just connects, loads the updates on its own internal memory stick, then plays audio even if the network cord is connected...everything becomes local at the unit after the audio is loaded to it.

Sorry Ed, I meant the unit does not need to be on the network in order to play MoH after the updates are loaded.

Definitely weird. Hope you find a cure.

Did You monitor the playback via BGM thru the system phone as i asked you to do ?

Sorry TJ, the location is 60 miles away from our technician, and he had not been back there yet...We kind of wanted to find a solution before we sent him out again.

Here is what we did today:
We redid the audio file andtotally removed the music...we only have the voice portion playing with no gaps. It sounds crystal clear. It almost seems as if the PRI is not translating the music frequency correctly!!

I Was looking thru a European SV8100 Release 9 Feature manual and came across this .

"It has been observed that some professional recording tools insert footer information to the saved wav
file. This footer can be intepreted as noise by the media player used by the SV8100. Please ensure that
the wav file does not contain any footer information prior to uploading the file. If necessary the footer can
be removed by using suitable text editing software similar to Notepad++."

Not sure if it's any help to the OP..