After inspecting the log files, the issue turned out to have been caused by the system clock going back and forth (the miner starts mining in year 2019, and then after a while the clock goes to 2036 which screws up scheduling engine used by the miner). If you could supply your log files so that I could look into whether your issue is caused by the same thing or not, that would be great. You can turn the logs on using "--protocol-dump -l trex.log" parameters as I suggested to bracinac. Thanks.