no ssb audio using ios app

Hi all,
My name is Frans and have the ham call PA5CA.
I have a question about the smart SDR IOS app.
All works fine with the IOS app but one annoying issue crack my brain.
I have zip TX SSB audio from the phone, The microphone is set to Iphone I have TX AM and TX FM audio but no way to get TX SSB audio from the Iphone
Perhaps some one recognize this and may have a solution.

Looking forward to the replies..

Yours, Frans de PA5CA