Subledger journals blank - showing up in Import Errors

We're seeing frequent increase in subledger import journals showing up in the GL Import Errors table, but the files are (seemingly) blank. We're unable to delete them from the Import Error table. Our solution has been to unfreeze the ledger source, open the blank error file, and then force an upload of the (seemingly) blank file. Is anyone else experiencing this? We have a work around, but trying to understand the front end cause/solution. Thank you.