Azure Document Intelligence batch jobs dropping ~18% of results with InternalServerError

We’re running batch jobs with Azure Document Intelligence using the .NET SDK (AnalyzeBatchDocumentsAsync). All source PDFs upload fine to Blob Storage, but about 18% of the documents fail with this error:

{

"SourceUri": "https://<account>.blob.core.windows.net/doc-intel-batch-source/AnalysisBatch_3/860.pdf",

"ResultUri": "https://<account>.blob.core.windows.net/doc-intel-batch-results/AnalysisBatch_3/860.pdf.ocr.json",

"Error": {

"Code": "InternalServerError",

"Message": "An unexpected error occurred."

}

}

The batch itself reports “Succeeded,” but those documents never show up in the results container. Retrying sometimes works, which makes it feel like a backend reliability issue rather than our setup.

Is anyone else seeing this kind of failure rate (~18%)? Any tips for stabilizing batch runs or getting more useful diagnostics out of the service?