Hi,
I use yam in Linux (ubuntu and Amazon) for XMR+FCN and after some time my shares start to get rejected with the following msg:
MINERGATE: Rejected share, reason: -15, Unknown job id
this becomes worse as time progresses
As mentioned the issue is known, it is due to minergate's protocol, and so far they have not responded to request to work with Yvg to sort out this issue. Best thing to do meantime is use a different pool for which you will get virtually 0% rejects over very long runtime
