Auto buffer size related to slow download?

[inetscan]

I'm noticing that about 1 in 5 downloads (from the same ftp, same types of files and sizes) will not get above 70KB/s while the remaining downloads have no problem staying between 2-5MB/s. A quick abort and transfer usually corrects the slow transfer. So I'm curious if the auto buffer size is potentially causing the slow transfers. When and how often does the tcp/ip buffer size change when set to "(auto)"? Is there any way to see the value of the buffer when it is being automatically configured? Any other idea on what might be causing this or how to diagnose? Thanks!

[MxxCon]

Highly unlikely that FlashFXP or your OS is doing that. It could be your ISP or some networking device.
Connect to this ftp using encryption or another port and see if you still have this problems.

[bigstar]

Using auto buffer size can result in better or worse performance, This method is intended for networks where conditions are always changing for better or worse and your transfer speeds range from very slow to extremely fast. If you're using Vista or Windows 7 this feature can hurt performance.

We recommend using default.

If you're trying to get optimal speeds unfortunately you wont be able to by adjusting the TCP/IP buffers in FlashFXP, We recently discovered an issue with this setting and anything but default will cause unexpected performance results.

The Receive TCP/IP buffer size is how much data can be held in memory waiting for the application to receive it, if the memory buffer is full it will not accept anymore data from the server until space is available.

The send TCP/IP Buffer size is how much data can be pending to send to the server, once the buffer is full it wont accept anymore data from the client, when space is available to send more data the application is notified and more data is put into the buffer.

[inetscan]

Thanks for the responses, I will continue digging.