Original Audio Issue

When using original Audio on my iPad or external microphone a hissing noise is now present. I have used zoom for two years without any of these issues. I am not sure why this recent update is making this happen. After viewing the discussion board multiple people are now having this same issue occur. 

I need assistance. I use the original audio for piano sessions and my business with over 50 students depends on having great-quality lessons. 

Any help would be much appreciated. 

Thank you.