How to find a stable port to open?

[schweinhundert]

I used to use the same old port, no problems, then recently switched over to 55641 having read that's what utorrent prefers. That worked ok a few days but just lately my download speeds have been abysmal, like 3-8 kB/s total. Ups are better, oddly, hovering at 10, where I've set them to be. (My crap dsl can't give me much more usually.)

So I thought maybe my ISP was choking that port or something so I switched back to my old port, and saw the speeds immediately jump back up where they should be. But they don't stay there, and taper off to super low again after 30 seconds or so. This happens each time I try changing ports, exactly the same way each time.

Any idea what's going on here? Is the boost I see just a glitch (I know some torrents will give a little initial boost when first loaded, similarly) or is my hardware doing something weird, or what?

Thanks for any help.

Does one port really make a difference over an other?

[Switeck]

So long as the port is above 10000 and below 65535, it hardly matters.

1st and 2nd links in my signature...you probably have other issues than a "bad" port.