I've noticed my ASI6200MM Pro will sometimes stop capturing images, suddenly after 39 successful exposures. NINA reports an error with GAIN -1 when the gain is set at 101. Below are my NINA logs of the last successful exposure and the following two attempted exposures.

I have noticed similar failures when doing manual exposures on the imaging tab.

How can I diagnose this problem?

2022-06-22T03:34:43.0650|INFO|SequenceItem.cs|Run|206|Starting Category: Camera, Item: TakeExposure, ExposureTime 420, Gain 101, Offset 70, ImageType DARK, Binning 1x1
2022-06-22T03:34:43.0720|INFO|CameraVM.cs|Capture|729|Starting Exposure - Exposure Time: 420s; Filter: ; Gain: 101; Offset 70; Binning: 1x1;
2022-06-22T03:34:44.0568|DEBUG|BaseImageData.cs|PrepareSave|110|Saved temporary image at C:\Users\PrimaLuceLab\Documents\N.I.N.A\Targets\7d7a417f-249d-45e8-95a3-85b789a8034d.xisf
2022-06-22T03:34:44.0568|INFO|BaseImageData.cs|FinalizeSave|153|Saving image at C:\Users\PrimaLuceLab\Documents\N.I.N.A\Targets\2022-06-21\DARK\2022-06-22_03-27-41_L-10.00_420.00s_0077.xisf
2022-06-22T03:34:44.0578|DEBUG|SessionMetaDataWatcher.cs|ImageSaveMeditator_ImageSaved|44|image is not a light, skipping
2022-06-22T03:34:44.0578|DEBUG|ImageSaveWatcher.cs|ImageSaveMeditator_ImageSaved|58|image type not enabled, skipping: DARK
2022-06-22T03:41:44.2724|DEBUG|ImageSaveController.cs|Enqueue|51|Enqueuing image to be saved with id 296
2022-06-22T03:41:44.2724|INFO|SequenceItem.cs|Run|224|Finishing Category: Camera, Item: TakeExposure, ExposureTime 420, Gain 101, Offset 70, ImageType DARK, Binning 1x1
2022-06-22T03:41:44.2724|DEBUG|ImageSaveController.cs|DoWork|60|Dequeuing image to be saved with id 296
2022-06-22T03:41:44.2734|INFO|SequenceItem.cs|Run|206|Starting Category: Camera, Item: TakeExposure, ExposureTime 420, Gain 101, Offset 70, ImageType DARK, Binning 1x1
2022-06-22T03:41:44.2794|INFO|CameraVM.cs|Capture|729|Starting Exposure - Exposure Time: 420s; Filter: ; Gain: 101; Offset 70; Binning: 1x1;
2022-06-22T03:41:45.2602|DEBUG|BaseImageData.cs|PrepareSave|110|Saved temporary image at C:\Users\PrimaLuceLab\Documents\N.I.N.A\Targets\c522df27-4010-43ce-a40d-a73250453119.xisf
2022-06-22T03:41:45.2602|INFO|BaseImageData.cs|FinalizeSave|153|Saving image at C:\Users\PrimaLuceLab\Documents\N.I.N.A\Targets\2022-06-21\DARK\2022-06-22_03-34-43_L-10.00_420.00s_0078.xisf
2022-06-22T03:41:45.2602|DEBUG|SessionMetaDataWatcher.cs|ImageSaveMeditator_ImageSaved|44|image is not a light, skipping
2022-06-22T03:41:45.2602|DEBUG|ImageSaveWatcher.cs|ImageSaveMeditator_ImageSaved|58|image type not enabled, skipping: DARK
2022-06-22T03:48:44.7311|ERROR|ASICamera.cs|DownloadExposure|409|ASI: Camera reported unsuccessful exposure: ASI_EXP_FAILED
2022-06-22T03:48:44.7341|ERROR|ImagingVM.cs|CaptureImage|225
NINA.Equipment.Exceptions.CameraDownloadFailedException: Camera download failed. Exposure details: Exposure time: 420, Type: DARK, Gain: -1, Filter:
2022-06-22T03:48:44.7341|ERROR|SequenceItem.cs|Run|233|Category: Camera, Item: TakeExposure, ExposureTime 420, Gain 101, Offset 70, ImageType DARK, Binning 1x1 -
System.NullReferenceException: Object reference not set to an instance of an object.
at NINA.Sequencer.SequenceItem.Imaging.TakeExposure.<Execute>d44.MoveNext() in E:\Projects\nina\NINA.Sequencer\SequenceItem\Imaging\TakeExposure.cs:line 188
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at NINA.Sequencer.SequenceItem.SequenceItem.<Run>d66.MoveNext() in E:\Projects\nina\NINA.Sequencer\SequenceItem\SequenceItem.cs:line 224
2022-06-22T03:48:44.7411|ERROR|SequenceItem.cs|RunErrorBehavior|193|Instruction failed after 1 attempt. Error behavior is set to ContinueOnError. Continuing.
2022-06-22T03:48:44.7441|DEBUG|Utilities.cs|GetFailedItem|184|Failed item: Take Exposure, Reason count: 1
2022-06-22T03:48:44.7501|INFO|SequenceTrigger.cs|Run|111|Starting Category: Ground Station, Item: FailuresToPushoverTrigger
2022-06-22T03:48:44.7550|DEBUG|PushoverCommon.cs|PushMessage|37|Pushing message
2022-06-22T03:48:45.3251|INFO|SequenceItem.cs|Run|206|Starting Category: Camera, Item: TakeExposure, ExposureTime 420, Gain 101, Offset 70, ImageType DARK, Binning 1x1
2022-06-22T03:48:45.3282|ERROR|ASICamera.cs|SetControlValue|623|Error occurred during set of ASI Control Value ASI_OFFSET:
ZWOptical.ASISDK.ASICameraException: Error 'ASI_ERROR_GENERAL_ERROR' from call to
ASISetControlValue(cameraId=0, controlType=ASI_OFFSET, value=70, auto=False)
at ZWOptical.ASISDK.ASICameraDll.CheckReturn(ASI_ERROR_CODE errorCode, MethodBase callingMethod, Object[] parameters) in E:\Projects\nina\NINA.Equipment\SDK\CameraSDKs\ASISDK\ASICameraDll.cs:line 284
at ZWOptical.ASISDK.ASICameraDll.SetControlValue(Int32 cameraId, ASI_CONTROL_TYPE controlType, Int32 value, Boolean auto) in E:\Projects\nina\NINA.Equipment\SDK\CameraSDKs\ASISDK\ASICameraDll.cs:line 327
at NINA.Equipment.Equipment.MyCamera.ASICamera.SetControlValue(ASI_CONTROL_TYPE type, Int32 value) in E:\Projects\nina\NINA.Equipment\Equipment\MyCamera\ASICamera.cs:line 617
2022-06-22T03:48:45.3340|INFO|CameraVM.cs|Capture|729|Starting Exposure - Exposure Time: 420s; Filter: ; Gain: 101; Offset 70; Binning: 1x1;
2022-06-22T03:48:45.6502|ERROR|ASICamera.cs|DownloadExposure|409|ASI: Camera reported unsuccessful exposure: ASI_EXP_FAILED
2022-06-22T03:48:45.6512|ERROR|ImagingVM.cs|CaptureImage|225
NINA.Equipment.Exceptions.CameraDownloadFailedException: Camera download failed. Exposure details: Exposure time: 420, Type: DARK, Gain: -1, Filter:
2022-06-22T03:48:45.6512|ERROR|SequenceItem.cs|Run|233|Category: Camera, Item: TakeExposure, ExposureTime 420, Gain 101, Offset 70, ImageType DARK, Binning 1x1 -
System.NullReferenceException: Object reference not set to an instance of an object.
at NINA.Sequencer.SequenceItem.Imaging.TakeExposure.<Execute>d44.MoveNext() in E:\Projects\nina\NINA.Sequencer\SequenceItem\Imaging\TakeExposure.cs:line 188
--- End of stack trace from previous location where exception was thrown ---
at System.Runtime.ExceptionServices.ExceptionDispatchInfo.Throw()
at NINA.Sequencer.SequenceItem.SequenceItem.<Run>d66.MoveNext() in E:\Projects\nina\NINA.Sequencer\SequenceItem\SequenceItem.cs:line 224
2022-06-22T03:48:45.6522|ERROR|SequenceItem.cs|RunErrorBehavior|193|Instruction failed after 1 attempt. Error behavior is set to ContinueOnError. Continuing.
2022-06-22T03:48:45.6532|DEBUG|Utilities.cs|GetFailedItem|184|Failed item: Take Exposure, Reason count: 1
2022-06-22T03:48:45.6532|INFO|SequenceTrigger.cs|Run|111|Starting Category: Ground Station, Item: FailuresToPushoverTrigger
2022-06-22T03:48:45.6552|DEBUG|PushoverCommon.cs|PushMessage|37|Pushing message
2022-06-22T03:48:45.9160|INFO|SequenceItem.cs|Run|206|Starting Category: Camera, Item: TakeExposure, ExposureTime 420, Gain 101, Offset 70, ImageType DARK, Binning 1x1
2022-06-22T03:48:45.9170|ERROR|ASICamera.cs|SetControlValue|623|Error occurred during set of ASI Control Value ASI_OFFSET:
ZWOptical.ASISDK.ASICameraException: Error 'ASI_ERROR_GENERAL_ERROR' from call to
ASISetControlValue(cameraId=0, controlType=ASI_OFFSET, value=70, auto=False)
at ZWOptical.ASISDK.ASICameraDll.CheckReturn(ASI_ERROR_CODE errorCode, MethodBase callingMethod, Object[] parameters) in E:\Projects\nina\NINA.Equipment\SDK\CameraSDKs\ASISDK\ASICameraDll.cs:line 284
at ZWOptical.ASISDK.ASICameraDll.SetControlValue(Int32 cameraId, ASI_CONTROL_TYPE controlType, Int32 value, Boolean auto) in E:\Projects\nina\NINA.Equipment\SDK\CameraSDKs\ASISDK\ASICameraDll.cs:line 327
at NINA.Equipment.Equipment.MyCamera.ASICamera.SetControlValue(ASI_CONTROL_TYPE type, Int32 value) in E:\Projects\nina\NINA.Equipment\Equipment\MyCamera\ASICamera.cs:line 617
2022-06-22T03:48:45.9180|INFO|CameraVM.cs|Capture|729|Starting Exposure - Exposure Time: 420s; Filter: ; Gain: 101; Offset 70; Binning: 1x1;
2022-06-22T03:48:46.2436|ERROR|ASICamera.cs|DownloadExposure|409|ASI: Camera reported unsuccessful exposure: ASI_EXP_FAILED
2022-06-22T03:48:46.2436|ERROR|ImagingVM.cs|CaptureImage|225