No sound Ubuntu 20.04 Lenovo AIO A540

For diagnostic purposes please follow
https://help.ubuntu.com/community/SoundTroubleshootingProcedure

I tried step1 and 2 without success

when I tried the step 3 I get some errors

horacio@horacio-IdeaCentre-AIO-5-24IMB05:~$ sudo apt update
[sudo] password for horacio:
Hit:1 http://ar.archive.ubuntu.com/ubuntu focal InRelease
Hit:2 http://ppa.launchpad.net/boltgolt/howdy/ubuntu focal InRelease
Get:3 http://ar.archive.ubuntu.com/ubuntu focal-updates InRelease [114 kB]
Ign:4 http://ppa.launchpad.net/ubuntu-audio-dev/alsa-daily/ubuntu focal InRelease
Err:5 http://ppa.launchpad.net/ubuntu-audio-dev/alsa-daily/ubuntu focal Release
  404 Not Found [IP: 91.189.95.85 80]
Get:6 http://ar.archive.ubuntu.com/ubuntu focal-backports InRelease [101 kB]
Ign:7 http://ar.archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata
Ign:8 http://ar.archive.ubuntu.com/ubuntu focal-updates/universe amd64 DEP-11 Metadata
Ign:9 http://ar.archive.ubuntu.com/ubuntu focal-updates/multiverse amd64 DEP-11 Metadata
Ign:10 http://ar.archive.ubuntu.com/ubuntu focal-backports/universe amd64 DEP-11 Metadata
Get:7 http://ar.archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata [282 kB]
Err:7 http://ar.archive.ubuntu.com/ubuntu focal-updates/main amd64 DEP-11 Metadata
  File has unexpected size (282396 != 282456). Mirror sync in progress? [IP: 200.236.31.4 80]
  Hashes of expected file:
   - Filesize:282456 [weak]
   - SHA256:768f0d2888ecb75ed591ce633f91b16ced4591f4c1c3018713d9bb7fb5ab4fb4
   - SHA1:e6711d68b29cb05a570bfe7a7e018d97dc8b1f5d [weak]
   - MD5Sum:bb8819961c5c336dba0f039096c6ca9c [weak]
  Release file created at: Sat, 21 Aug 2021 23:03:52 +0000
Get:8 http://ar.archive.ubuntu.com/ubuntu focal-updates/universe amd64 DEP-11 Metadata [351 kB]
Err:8 http://ar.archive.ubuntu.com/ubuntu focal-updates/universe amd64 DEP-11 Metadata

Get:9 http://ar.archive.ubuntu.com/ubuntu focal-updates/multiverse amd64 DEP-11 Metadata [940 B]
Err:9 http://ar.archive.ubuntu.com/ubuntu focal-updates/multiverse amd64 DEP-11 Metadata

Get:10 http://ar.archive.ubuntu.com/ubuntu focal-backports/universe amd64 DEP-11 Metadata [10,3 kB]
Err:10 http://ar.archive.ubuntu.com/ubuntu focal-backports/universe amd64 DEP-11 Metadata
  Hash Sum mismatch
  Hashes of expected file:
   - Filesize:10324 [weak]
   - SHA256:e4c0bdca0abaad87267b2e4722f8f9521396e0985e4e07bd17e4caf0c6222795
   - SHA1:eb9d21b4cf4f25d3c352bedd8555b080c06b37b4 [weak]
   - MD5Sum:375aa9b7c5c57107bf676affc961a268 [weak]
  Hashes of received file:
   - SHA256:fa9aeb01ee8dc615bde46304e71849e9d2b73eb436be6ebecb2b8592e0f47a79
   - SHA1:4de41ea726edef8dc707a8d234bc12e28ef3302f [weak]
   - MD5Sum:e7e3c24c86181e42a6539f7d17cbcae5 [weak]
   - Filesize:10324 [weak]
  Last modification reported: Sat, 21 Aug 2021 19:19:50 +0000
  Release file created at: Sat, 21 Aug 2021 23:04:29 +0000
Hit:11 http://dl.google.com/linux/chrome/deb stable InRelease
Get:12 http://security.ubuntu.com/ubuntu focal-security InRelease [114 kB]
Hit:13 https://packages.microsoft.com/repos/ms-teams stable InRelease
Reading package lists... Done
E: The repository 'http://ppa.launchpad.net/ubuntu-audio-dev/alsa-daily/ubuntu focal Release' does not have a Release file.
N: Updating from such a repository can't be done securely, and is therefore disabled by default.
N: See apt-secure(8) manpage for repository creation and user configuration details.

Should I change this repository?
thanks for your help

I see two different issues:

1. The instruction to add ppa:ubuntu-audio-dev/alsa-daily is not valid for Ubuntu releases after bionic and you should remove that entry again:

sudo apt-add-repository --remove ppa:ubuntu-audio-dev/alsa-daily

2. There is a checksum error in the files that you download from the ar.archive.ubuntu.com repository server. This can be caused by errors on the server, something going wrong on the network connection, or something on your system.

I suggest that you just try again now. If you still get similar error messages, I suggest that you try switching to a different repository server, e.g. zero.com.ar or the central server.