Yeah so the sound is leaking out of your mold or dome more then it can handle, need to get a tight fit for good results, possibly could be a wax issue, but I’d try a good fit to begin with.
It means you need a better fit between your dome or mould and you ear and so it’s not possible for the feedback suppression to prevent feedback at the moment.
Thanks for reply. I added more details for your analysis.
My left aid is success for calibration quickly in one time, but the right one failed even I tried different size domes for several times.
It can perfectly calibrated before. The issue just come in this month.
Do you have any further thoughts?