It seems from this log that you are successfully connecting to the SSH server, but not authenticating properly. Are you sure that there is nothing in /var/log/messages, /var/log/secure, /var/log/sshd or any similar file?
key_type_from_name: unknown key type '-----BEGIN'
This like looks like the start of a public or private keyfile, and the error seems to indicate that the file format is wrong. This looks to be a similar message to some other reports of keys generated with old/incompatible versions of the keygen program (http://www.linuxquestions.org/questi...y-type-277341/
It seems likely that the public key on the server matches the private keys on the other machines, but not the other way around. Try taking a look at the ~/.ssh/id_?sa files on each machine and make sure that the formats look to be the same.
If not, you may need to regenerate the keys to fix this.
The other thing to check is the configuration of the SSHD server on the machine you can't connect to. Make sure that logins are not disabled for the user you are logging in as (gabrix) and that you can actually log in as this user on the console.
Not exactly a solution, but I hope that helps you to find some more information about the problem.
—Robert J Lee