Adobe PDF Embed API Caching Issues showing older Annotations

HI Team,

We are using PDF Embed API/ PDF viewer service to use for Annotations on PDF. We are able to annotate and Save the document to AEM. On refresh of a PDF page on browser after sucessfull Save operation to Post data to AEM, we are still seeing older version of the comments within PDF. We are able to see latest set of comments on using Ctrl + Shift + R but not with normal refresh of a PDF Annotated page. 

We have also verified in AEM to see if server has latest set of comments persidted with in document and it has latest comments.

I have taken into consideration qand implemented below points

1. Remove the iframe src and refresh PDF page for every Save operation to Server to make sure iframe loaded with PDF is always a non cached version on browser and gets latest from Server.
2. No Dispatcher cache for PDF files from Server side.
3. Clearing localstorage of browser to make sure each refresh gets a fresh version of PDF which is stored in AEM.

Can you please kindly support me to address this issue ?

Thanks,

Puneeth.