I really would like to help you but I need more details.
What drive? (brand and type) this is this Western Digital 500Gb?
USB powered or external powered?
Do you using any USB extension cable?
Does the drive formatted with uTrack?
How many takes on the drive?
Do you have isolated the environment resonance by putting some soft material below the drive? I mean If there’s a loud music especially low frequencies that can be transferred to the drive, then the internal protection mechanism put the heads to parking position to protect the drive, this can cause that kind of dropouts what you described. I found the WD drives are really sensitive for the resonances.
Could you please make a test recording in a quiet environment to make sure not the resonance cause that problem?
As you had problem with importing as well could you please try to record to another drive and import the data from that drive?
(make sure the drive formatted with uTrack before you starting to record to the drive)