[chirp_users] Can't add repository

Hi, I have done this many times before, I don't know if the error is coming from the site or if it means something is amiss with my system. I just today installed Ubuntu Mate 16.4.3 onto USB and ran an update. Than in a terminal, I ran: sudo add-apt-repository ppa:dansmith/chirp-snapshots and I get the error: input output error

and the PPA isn't added. Any thoughts?

Lenny/Glenn/N0YJV

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