No, I have not had that problem at all this tax season.  

But a tag along issue I have is this:  A client who fails the authentication should know why.  Do they get a message?  Does the message assist them in authenticating?  Yesterday, I logged into DocuSign for a client and there was no reason provided for the authentication failure.

The reason they fail authentication is they answer a security question wrong. I don't think they get another chance at it. To my knowledge you have to resend the docusign.

And they get three tries (the first and then two void-and-resends on the preparer end) and then they are stuck with a wet ink signature for that year.

Do they know which authentication question is not correct?

Yes, I think it gives them the failed notice after the question they answer wrong.