Thanks for your reply. I understand that I need to disable some PPA, but it seems that oibaf doesn't do the trick. When I run 'sudo ppa-purge oibaf', I get the following output:
Updating packages lists
W: There is no public key available for the following key IDs:
1397BC53640DB551
PPA to be removed: oibaf ppa
Warning: Could not find package list for PPA: oibaf ppa
Is there any other PPA that I should try to disable?
Thanks for your reply. I understand that I need to disable some PPA, but it seems that oibaf doesn't do the trick. When I run 'sudo ppa-purge oibaf', I get the following output:
Updating packages lists
W: There is no public key available for the following key IDs:
1397BC53640DB551
PPA to be removed: oibaf ppa
Warning: Could not find package list for PPA: oibaf ppa
Is there any other PPA that I should try to disable?