Just today I’m getting errors when trying to install software via apt in Debian 13. Specifically ardour and gnome-boxes. Other packages seem to be unaffected, like gimp and blobwars for example. The errors are all variations of the following:

Err:1 http://deb.debian.org/debian trixie/main amd64 libwebsockets19t64 amd64 4.3.5-1 404 Not Found [IP: 151.101.62.132 80] Error: Failed to fetch http://deb.debian.org/debian/pool/main/libw/libwebsockets/libwebsockets19t64_4.3.5-1_amd64.deb 404 Not Found [IP: 151.101.62.132 80]

Looking online the suggestion seems to be that I might have /etc/apt/sources.list misconfigured. Is it this causing the problem, or something else?

Here is my sources.list

# deb cdrom://[Debian GNU/Linux 13.0.0 _Trixie_ - Official amd64 NETINST with firmware 20250809-11:2>

deb http://deb.debian.org/debian/ trixie main non-free-firmware 
deb-src http://deb.debian.org/debian/ trixie main non-free-firmware 

deb http://security.debian.org/debian-security/ trixie-security main non-free-firmware 
deb-src http://security.debian.org/debian-security/ trixie-security main non-free-firmware 

# trixie-updates, to get updates before a point release is made;
# see https://www.debian.org/doc/manuals/debian-reference/ch02.en.html#_updates_and_backports
deb http://deb.debian.org/debian/ trixie-updates main non-free-firmware 
deb-src http://deb.debian.org/debian/ trixie-updates main non-free-firmware 

# This system was installed using removable media other than
# CD/DVD/BD (e.g. USB stick, SD card, ISO image file).
# The matching "deb cdrom" entries were disabled at the end
# of the installation process.
# For information about how to configure apt package sources,
# see the sources.list(5) manual.

Any advice?

Thanks!