Audio suddenly super low

[Truls27995341xyka]

I was working on a video and everyhing was fine, I exported a small section, suddnely I realise that the audio is super super low, barley audible. I have no idea how that happend, I've tried a render and replace, I've tried to increase the volume of the clips, nothing works, If I start a new project the audo is fine. 

But I've spent hours on this project already. 

I've tried a restart on the PC, no effect. Goolge does not help at all.

[Averdahl]

Maybe you have by mistake dragged down the white/grey line in the Mix and/or a track on the timeline?

If you hover the mouse on it it should say "...Volume 0,00 dB". If you see anything lower than 0,00 dB indicates that you have by mistake adjusted it.