WCF streamed response failing on large data

Question

I'm currently experiencing an issue using WCF streaming to return a large set of serialized objects over the internet while hosted through IIS. I'm not sure if it is a network issue or a WCF issue, but the symptoms are hard for me to justify as network issues, as I'll describe below.

The objects are a variety of different objects sent over the one stream, most of which are small but there are also jpegs in there which range from 10k->500k per object. The different cases that I can't really reconcile are:

1. If we run it over our internal network it works perfectly, even if we increase the data transferred 10-fold higher than the real case so we're sending gigabytes of data.
2. If we run it on the servers hosting the solution we get an error (detailed below) after a few minutes and a few hundred megabytes transferred.
3. If we run it on the servers but remove the photos (Sending only the other data) it succeeds and sends roughly 40mb over a longer time period than the failure takes (The longer time is because it takes longer to process the other data, so that's expected).
4. We have tested simply downloading a 1GB file off the webserver (Significantly more than any of the tests other than the ones we tried on our local network) and it succeeded multiple times without issue.

The error we receive client-side is (Note: We went nowhere near the 3 hour timeout we have set):

System.Reflection.TargetInvocationException: An exception occurred during the operation, making the result invalid. Check InnerException for exception details. ---> 
System.ServiceModel.CommunicationException: The socket connection was aborted. This could be caused by an error processing your message or a receive timeout being exceeded by the remote host, or an underlying network resource issue. Local socket timeout was '03:00:00'. ---> 
System.IO.IOException: Unable to read data from the transport connection: An existing connection was forcibly closed by the remote host. ---> 
System.Net.Sockets.SocketException: An existing connection was forcibly closed by the remote host

And server-side we see:

System.ServiceModel.CommunicationException,
System.ServiceModel, Version=3.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089 The remote host closed the connection. The error code is 0x80070016.

The WCF binding setup is (With a little anonymizing):

  <system.serviceModel>
    <serviceHostingEnvironment>
      <baseAddressPrefixFilters>
        <add prefix="http://anonymous"/&gt;
      </baseAddressPrefixFilters>
    </serviceHostingEnvironment>
    <bindings>
      <basicHttpBinding>
        <binding name="StreamedHttpBindingConfig" transferMode="StreamedResponse" maxReceivedMessageSize="2147483647" maxBufferSize="8388608" sendTimeout="01:00:00">
          <readerQuotas maxStringContentLength="2147483647" maxArrayLength="2147483647"
            maxBytesPerRead="2147483647" maxNameTableCharCount="2147483647" maxDepth="2147483647" />
          <security mode="None" />
        </binding>
      </basicHttpBinding>
    </bindings>
    <services>
      <service behaviorConfiguration="wsHttpBindingBehaviour" name="AnonymousName">
        <endpoint address="" binding="basicHttpBinding" bindingConfiguration="StreamedHttpBindingConfig" name="wsHttpBinaryBindingEndpoint" contract="Service.IAnonymous" />
        <endpoint address="mex" binding="mexHttpBinding" name="mexHttpBindingEndpoint" contract="IMetadataExchange" />
        <host>
          <baseAddresses>
            <add baseAddress="http://anonymous/Service" />
          </baseAddresses>
        </host>
      </service>
    </services>
    <behaviors>
      <serviceBehaviors>
        <behavior name="wsHttpBindingBehaviour">
          <serviceThrottling maxConcurrentCalls="160" maxConcurrentSessions="100" maxConcurrentInstances="100" />
          <dataContractSerializer maxItemsInObjectGraph="2147483647"/>
          <serviceMetadata httpGetEnabled="true" />
          <serviceDebug includeExceptionDetailInFaults="true" />
        </behavior>
      </serviceBehaviors>
    </behaviors>
  </system.serviceModel>

And the service contract is (Method/param names changed to anonymize, but types the same):

System.ServiceModel.Channels.Message GetData(System.ServiceModel.Channels.Message request);

Which looks like a network issue to me, but I can't imagine why it would succeed on the longer time-period with smaller data if it was intermittent network issues and I can't see why downloading a large file would've been unaffected if this was the case. Does anyone know a potential cause for this, or any idea what the next step of diagnosing it is?