*** Solution*** At least for me anyway. I tried all of the suggestions without any effect and would still get an error as described by OP. To me it seems that the issue is relating to how Mac handles memory. I had photoshop open with a few photos. Two things happen, I was very low on disk space but had enough to download the video I needed thought but closed photoshop so that it can free up disk space as it normally uses a considerable amount of swap and free disk space. As soon as I closed it, I saw my disk space go from under 2 gb free to 15 gb free and my swap have less on it (using activity monitor).
I did nothing else NOTHING else this time around and it transferred flawlessly. Here is my theory, when transferring it probably buffers to a temp file while transfering if your RAM is low and if your swap space can't grow or the temp file can't be written due to disk space problems the video will just error out. I will test this theory by opening photoshop, a bunch of .psd files to fill up swap but also delete some files so that I have more than enough for the transfer 3 times and see that happens. Them I will make sure that I have no disk space (except for the amount needed for the file 2 times) but plenty of space in the swapfile and see which one of the two fails.
Hope this helps someone. So in conclusion, have plenty of disk space available and close all programs and the transfer will work.
Art