Overloading a preamp input question

I’ve recently run into a situation where a dac w it’s volume control bypassed overloaded my preamps line stage input. I’m assuming that in bypass mode the dac is outputting full gain which is thought to be 9v. Is that a lot? I’ve never had this scenario before. I believe that std output for most cd players in balanced mode is around 4v.
Im thinking that a tech guy on this site can provide some input. thanks