I would not recommend amending anything. Let the audit process take its course. Amending will only complicate things.
The IRS volume is higher than they have the staffing to support and as a result it could take some time. Just make sure you read what you are sent, if you don't understand it, ask if you have the ability to speak with the IRS in person again or get in touch with a tax professional who can provide some assistance.
If you missed reporting something, then as noted above, just agree to the change(s). Generally not the end of the world, since most mistakes are not done to avoid or evade the tax laws.
*A reminder that posts in a forum such as this do not constitute tax advice.
Also keep in mind the date of replies, as tax law changes.
