Q:
Xone:62 - Can I convert my phono inputs into line inputs?

A: 
Yes, this is possible, but not a user option and it is not as straightforward as the Xone:92 which can be done by changing jumper positions.
For the Xone:62 you will need to send your mixer to an approved A&H distributor or their service agent to perform the modification.

You might invalidate your warranty if work is carried out by unqualified service personnel.