Speakup on the newest Gentoo minimal cd doesn't works with any boot parameters

[Charaya]

Hello Speakup users,
I want to instal Gentoo with my Mac, but I need a screenreader to install it. I didn't get brltty working and speakup isn't working to. I tried all speakup boot parameters (speakup.synth=synth) I don't know what to do now.
I had talking arch live cd on a disk but my dvd device isn't working anymore so I have the gentoo minimal cd on my stick because dd can't write big files on any stick here. But there on talking arch I had to select the right soundcart - it was not the first avaylable - maybe I have to select the right soundcart on gentoo too? But how?
Does anibody  has got an idea?
Best regards,
charaya

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