How to access hidden volume in Technics DVD-A10?

How do you access the hidden volume control in
the Technics DVD A-10 DVD player? I want to hook
the player directly into my Audio Research amplifier.
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If you read through the 100 page instruction book you will find the set of remote controlled menus taht control the various adjustments the A10 can do. I am at work so I cannot tell you key by keystroke what to do. But if no-one else does by the time I get home this evening, I will post the instructions.
I am original owner of an A-10

On the remote, push display twice..toggle left. Toggle up or down to control volume.

Thank's sogoo51!