<snip>
>
> Most of audio programs in arch-linux (I think its the same at other distros)
> were provided from the community, here AUR. This is in one hand  positive
> and innovative. But it brings on the other side instability, like in our
> case and we are in a production.
>
> My questions are how can i find older versions of this programs
> (glib/glibmm/guitarix) until the bug is fixed or how I can handle in future
> a "last best system" ?

That's a question for the arch ML/forums/IRC, not here. Arch's wiki
has an article about downgrading, you should start there. However, as
an Arch user myself, downgrading glib alone not at all supported, its
rolling release after all.

Yes its a rolling release this makes it sometimes difficult. I remembered what I changed, it was guitarix2 instead of guitarix. So I restored the guitarix and Rosegarden is running now without downgrading.

Thanx for the hint of downgrading in Arch-Linux, I have to go through it and have to make some more checks before the easy upgrade in Arch linux.

Yosef