For the last ~day the difference between the frontend GPS time and the machine GPS time remained constant between -1 and -2 seconds

I reconnected the DAC timing cable at
PST: 2016-12-08 09:23:06.934999 PST
UTC: 2016-12-08 17:23:06.934999 UTC
GPS: 1165253003
After that, the timing started to drift at a rate of about 1 second every 2300 seconds (4.35e-4). So the conclusion is that the culprit for the timing issue is on the DAC connection side.

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