You can remove that effect simply by making the packet size large enough to send the whole image at once, I would think (it did in my tests) - but as noted, this could lead to network congestion if you are sending very large packets very frequently from lots of machines.
There isn't anything to "fix" here though as nothing is broken :) The data has to be sent across in chunks of some size... I guess the only way to change it would be to make the packets a whole number of the data size required for the entire image at once, but that would be a feature request rather than a fix. It certainly has no impact on the final image or result or rendering speed.
