I have the same problem:
GTX 1070

Graphrate is unstable!


[INFO] [2019-01-27T17:14:28-04:00] Received new job 62
[ERRO] [2019-01-27T17:14:29-04:00] Failed to fetch device Status for device id: 0, Error code: 999
[WARN] [2019-01-27T17:14:29-04:00] Rejected share #0 ({"code":10,"message":"invalid share: share context is invalid!"})
[ERRO] [2019-01-27T17:14:31-04:00] Failed to fetch device Status for device id: 6, Error code: 999
[ERRO] [2019-01-27T17:14:33-04:00] Failed to fetch device Status for device id: 7, Error code: 999
[INFO] [2019-01-27T17:14:42-04:00] Received new job 63
[INFO] [2019-01-27T17:14:48-04:00] [GPU 0] Speed: 2.36 G/s Fidelity 0.904 Temp:  1C Fan: 1% Power: 1W 2.36 G/J
[INFO] [2019-01-27T17:14:49-04:00] [GPU 1] Speed: 1.97 G/s Fidelity 0.877 Temp:  1C Fan: 1% Power: 1W 1.97 G/J
[INFO] [2019-01-27T17:14:49-04:00] [GPU 2] Speed: 1.44 G/s Fidelity 0.832 Temp: 42C Fan: 69% Power: 42W 0.03 G/J
[INFO] [2019-01-27T17:14:50-04:00] [GPU 3] Speed: 2.17 G/s Fidelity 0.905 Temp: 44C Fan: 70% Power: 109W 0.02 G/J
[INFO] [2019-01-27T17:14:51-04:00] [GPU 4] Speed: 1.49 G/s Fidelity 0.810 Temp: 40C Fan: 71% Power: 39W 0.04 G/J
[INFO] [2019-01-27T17:14:51-04:00] [GPU 5] Speed: 1.83 G/s Fidelity 0.876 Temp: 42C Fan: 71% Power: 136W 0.01 G/J
[INFO] [2019-01-27T17:14:52-04:00] [GPU 6] Speed: 2.06 G/s Fidelity 1.002 Temp:  1C Fan: 1% Power: 1W 2.06 G/J
[INFO] [2019-01-27T17:14:52-04:00] [GPU 7] Speed: 2.04 G/s Fidelity 0.739 Temp:  1C Fan: 1% Power: 1W 2.04 G/J
[INFO] [2019-01-27T17:14:57-04:00] Received new job 64
[ERRO] [2019-01-27T17:14:59-04:00] Failed to fetch device Status for device id: 0, Error code: 999
[ERRO] [2019-01-27T17:15:08-04:00] Failed to fetch device Status for device id: 6, Error code: 999
[ERRO] [2019-01-27T17:15:10-04:00] Failed to fetch device Status for device id: 7, Error code: 999
[INFO] [2019-01-27T17:15:12-04:00] Received new job 65

Any suggestions?