Warning in FragmentMetadataVisitor class

[srushti9999]

I am trying to process an audio recorded from a Contact flow of Amazon connect instance using Kinesis Video Streams.
We get the output from GetMedia as 200 as can be seen below:
INFO KVSUtils:GetMedia called on stream 'stream-name' response 200 requestId ''

But when the file is converted to wav, it is showing file size as 0.
I am getting no errors in the cloud watch logs. Only the below warning:

WARN FragmentMetadataVisitor:Segment end MkvEndMasterElement(super=MkvElement(elementMetaData=EBMLElementMetaData(typeInfo=EBMLTypeInfo(id=id_value, name=Segment, level=0, type=MASTER, isRecursive=false), elementNumber=4), elementPath=[])) while in PRE_CLUSTER. Collecting cluster info

When checked, this warning comes from the FragmentMetadataVisitor.java file.
I want to know in which scenarios will this warning be thrown, so I can understand if that is causing the issue.

Thanks!