Backup keeps pausing

Question

Using a 1TB TC connected to my MacPro via 802.11n only, 5GHz, wide channels on.
For example, a simple 50MB backup will stop at 40MB, go so, pause for several minutes, then pick up again. There really is no pattern to it. It just seems to stall at times.
When this happens, my internet connection is perfectly fine. I have tried other network configurations (ie b/g compatible, wide channels off, 2.4GHz) to the same result.

Answer 1

This procedure is a diagnostic test. It makes no changes to your data.
Please triple-click anywhere in the line below on this page to select it:
{ diskutil list; echo; diskutil cs list; } | pbcopy
Copy the selected text to the Clipboard by pressing the key combination command-C.
Launch the built-in Terminal application in any of the following ways:
☞ Enter the first few letters of its name into a Spotlight search. Select it in the results (it should be at the top.)
☞ In the Finder, select Go ▹ Utilities from the menu bar, or press the key combination shift-command-U. The application is in the folder that opens.
☞ Open LaunchPad. Click Utilities, then Terminal in the icon grid.
Paste into the Terminal window by pressing the key combination command-V. I've tested these instructions only with the Safari web browser. If you use another browser, you may have to press the return key after pasting.
Wait for a new line ending in a dollar sign ($) to appear below what you entered.
The output of the command will be automatically copied to the Clipboard. If the command produced no output, the Clipboard will be empty. Paste into a reply to this message.
The Terminal window doesn't show the output. Please don't copy anything from there.
If any personal information appears in the output, anonymize before posting, but don’t remove the context.