I recommending wait it decreasing until like 1ghs 
and hire technician to fix it.
I remembered i fix it when my ghs down to 7. Feel like not worth it..
You can buy or hire technician for that fix.
By waiting for the miner to go all the way down to 1 GHs then half way there, his earnings would be on the negative side since there would be maintenance cost and Electricity cost each day and he earns lesser each day too so I recommend to fix at most 5 GHs the miner in order to be on the positive earning side and hire technician to fix it.I remembered i fix it when my ghs down to 7. Feel like not worth it..
You can buy or hire technician for that fix.
Aliser: After I repaired my miner since last time, on the dashboard it's showing full hash power instead of the real one that is displayed on the inventory tab which at the moment is at 95% ... kindly do check this problem since it's misleading, thank you
I would do it at 64.99% myself (this would round down to 60%) to maximize profit. The earnings should more than cover renting a techn.