Howdy!

Recently, I’ve aquired an Aura CA-200 preamp, and it has 1 button which I can’t seem to figure out: Mode. When I press it once, the display shows the current input followed by T1 -> T2, e.g. LINE_4 T1 -> T2. Press it again, it switches to LINE_4 T2 -> T1, and for a 3rd click, it shows LINE_4 LOCK. After a 4th push of the button, it just returns to LINE_4.

Via another site, I was able to find the service manual for this preamp, yet it doesn’t seem to provide any insight. Since hifiengine.com registrations are closed, I was hoping to find someone with access to help me out.

Cheers