Thanks for the answers!

I think, I will not install the "Screen Recorder" app because first, it does not record sound (but that is what I need in the first place) and second, because it needs "Full System Access" rights to be installed. I think, access to the screen, to the sound and to the user's files in the user's directory should be enough. I do not see, why full system access is needed.

In the comments of the Screen Recorder app i saw the comment "works great, thank you, no longer have to record my remote desktop". Maybe this is a solution for me. Does anybody know how to connect to a UT phone via remote desktop?

(Another solution, which would be fine for my use-case, would be to simply record only the sound. Is this possible in some way?)

How can I record a screencast with a smartphone which runs with Ubuntu Touch? I want to record the complete screen for about 20 seconds including sound.
(I own a Volla Phone Quintus with UT 20.04 OTA-9, but I think, this does not matter in this context)

Currently only the subcategories "Volla Phone", "Volla Phone 22", "Volla Phone X" and "Volla Phone X23" exist. For example: the Volla Phone X23 has comments in this forum in https://forums.ubports.com/category/118/volla-phone-x23

Does anyone have experience with a wireless connection that connects a Volla Quintus with a monitor? If yes, which monitors work and which don't?

In this forum the subcategory "Devices/Volla/Volla Phone Quintus" is still missing and should be created.

@Charly , this problem seems not to happen to every volla. So, if I understand you correctly: you had these problems and they went away for months now?

Hi @AppLee , yes, I wrote a mail and got an answer yesterday.

They say that these screens are not available anymore and that a screens swap would cost 120 Euros anyway. They also wrote that I can get a new Volla with 20 % discount on the regular price. But I think, they are not really addressing this problem and I do not want to have the same problem again in about 1 or 2 years.

@sven , following your advice, I removed the SIM card and restarted the vollaphone. The problems did not go away. I restarted again and tested again in a time of about 24 hours. The result was that the problems did not go away.
Now I use my vollaphone with the SIM card again. But I really must find a solution, because as time goes on the phone gets more and more unusable.

@Ian , maybe it's a problem of the original Vollaphone and not of Vollaphone X. Or something, which we did not find out yet, triggers this problem after some months of usage. I also did not have these problems from the start.

Has anyone found a solution (or a workaround) for the ghost touches problem? (The funny thing is: I already owned my Volla for a year before the problem surfaced. Now, with time or with each update, the problem seems to get worse)