Video upload & show: org.apache.catalina.connector.ClientAbortException: ja

I implemented a video upload and play function for mp4-videos in my application.
Often (but not always) I get the the following exception after clicking “Exec import” in the pop up window
and the video is not shown (text something like “no video with supported format … found” is shown instead).
Nevertherless after clicking “Exec import” (which moves the file from “tmp” to “video” and gives it another name)
and clicking “Show video” in the main window, the video is shown correctly

I have the impression that this is somehow connected to the size of the video file.
For files of size 44 Mb I get the exception very often, 4 Mb files seem to work all times.

While this does not seem to be a Vaadin problem, I would be grateful if somebody has made
similar experiences and found a solution.

I use Vaadin 7.6.7, Tomcat 8.0.21.
I also attach a WAR-file with a stripped down version of my source code.

org.apache.catalina.connector.ClientAbortException: An existing connection was forcibly closed by the remote host
at org.apache.catalina.connector.OutputBuffer.realWriteBytes(
at org.apache.tomcat.util.buf.ByteChunk.append(
at org.apache.catalina.connector.OutputBuffer.writeBytes(
at org.apache.catalina.connector.OutputBuffer.write(
at org.apache.catalina.connector.CoyoteOutputStream.write(
at com.vaadin.server.DownloadStream.writeResponse(
at com.vaadin.ui.AbstractMedia.handleConnectorRequest(
at com.vaadin.server.ConnectorResourceHandler.handleRequest(
at com.vaadin.server.VaadinService.handleRequest(

Caused by: An existing connection was forcibly closed by the remote host
at Method)

Somehow the attachment seems to be lost in my original post, so I add it here again.
29418.war (16.7 KB)

I am getting the same error, when I open the Vaadin app in the browser. It does not seem to affect the user experience, but it bloat logs. It does seem to be a vaadin issue over here.