MK4 UI issue: Very slow file transfer, often resulting in timeout  

MK4 UI issue: Very slow file transfer, often resulting in timeout

I built an MK4 from a kit about a week ago and have printed about 20 models with it. So far, I am extremely pleased with the quality of the hardware and the resulting prints. However, the firmware and web interface definitely need some help. I have noticed about six serious bugs so far, and I am creating one thread for each of them to start a discussion.

Issue: Very slow file transfer, often resulting in timeout

Transferring files to and from the MK4 is often very slow - on the order of 100kb/second or less.

In general, slow transfer speeds are merely an annoyance, but the issue becomes more significant when transfers of larger files (> 20mb) result in a timeout. On several occasions, I have had to retry file transfers due to timeout issues. For one model that involved a 20mb file, repeated attempts failed, and I needed to retrieve the flash drive and copy the file manually.

The issues also occur for downloads of files stored on the printer - six attempts to download a 20mb file have all failed with timeout messages.

The odd part of this behavior is that the web interface is generally very snappy and responsive; it does not show the same dialup-quality connection issues as file transfer. Only file transfer operations appear to exhibit these performance issues.

Frequency: This performance issue applies to nearly all file transfers in either direction.

Software environment: The MK4 is running the latest firmware (4.7.0).