IVR has hissing sound silence

When i call my IVR from an external source, i get a very noisy hissing sound in the beginning before the IVR starts. If i call back immediately a few times, it doesnt happen. There is no silence on my IVR recording, it’s something being added by asterisk. I think it may have something to do with transcoding, my IVR is in WAV format, i cannot seem to upload any other format, if I upload MP3, it gets converted to wav.

Any ideas? It sounds awful and wouldnt want outside callers to hear that.


My fist thought would be echo training but you really have not provided enough information for anyone to help you.

Thanks for your reply Alan, what kind of information would help diagnose this issue? This hissing sound happens where ever there is silence in the system. So for example, when my IVR announcement finishes and the user hasnt pressed a button, there is silence waiting for a user to press a digit. During this silence i get this exact same annoying hissing sound. I dont mind the silence but the hissing is what sounds horrible.

Please check out the following post. It has some guidelines of what is helpful.

Without detail my knee jerk reaction is the Non-linear processor mode (type)