At stopAI:
I am using terminus-fonts, but the framebuffer uses the 4k-resolution, which makes the signs on the
screen too small, also when using 32x16.

At steve_v
Of course I am using a great console font. That's why I tried something else.
I found the "solutions" on special websites to help linux users. In this forum there was no topic,
The graphics were not touched, the only problem was the blocking of the digital parts of audio, so I
did not think of the effect on the kernel - thank you for that hint.
When installing devuan on my pc (or starting for example a Knoppix live-DVD) I am forced to change
the start parameter to vga=normal. If not, the framebuffer function draws funny lines on the screen
(Asus mainboard, AMD ryzen 3, radeon chip). So I did not expect what has happened,

Finally you explored the reason of the sound problem, but you offered as a solution to change the
size of the font what I have done.

Just install package

xfonts-terminus

and reconfigure konsole with

sudo dpkg-reconfigure console-setup

grub cuts the sound...
GRUB_CMDLINE_LINUX_DEFAULT="vga nomodeset"...
At the moment I am thinking to change to lilo

GRUB has nothing to do with anything. You are passing 'vga nomodeset' to the kernel, which will disable KMS and considerable functionality of your graphics drivers (likely forcing some VESA compatibility mode which knows nothing about HDMI or audio).
Whether you do that with GRUB, LILO, or some other bootloader is irrelevant.

'nomodeset' doesn't "fix" anything and has nothing to do with the size of "letters on tty1", besides forcing some miserable (probably 640x480) fallback video mode. It's a "boot with minimal graphics capabilities and don't try to set a video mode" troubleshooting tool.
Perhaps consider reading the documentation for the kernel command-line switches you pass, rather than copy-pasting random things from the internet?

If what you really want is a different console font, change the console font. See 'man console-setup', 'dpkg-reconfigure console-setup', and/or '/etc/default/console-setup'.

finding out what happened I was rather surprised.

My system: daedalus, I'm not using a UEFI-partition, grub.

I connected my pc with a 4k-TV. Everything was fine, except the very small letters on tty1 etc.,
caused by the high resolution. I found hints changing /etc/default/grub, setting
GRUB_GFXMODE="wished resolution"; this had an effect on the graphic start window of grub, but not to
an tty. Using GRUB_GFXPAYLOAD_LINUX=keep should have an effect on the terminals - I saw none.

Finally I found the information, to set
GRUB_CMDLINE_LINUX_DEFAULT="vga nomodeset".

Indeed, the letters on tty1, tty2 etc. had the wished size. But the switch from "family" to "raven"
on pulse was not possible. Clicking on the configuration I saw: HDMI not connected; I saw the
picture without sound.

Changing /etc/default/grub to the original value had the effect, that the switch-possibility
reappeared, HDMI was connected again.

At the moment I am thinking to change to lilo ...