I get echo posts from myspace and facebook to my twitter page.

There's some kind of echo when I post to ping.fm. I'm set up for a facebook page, twitter, and myspace. When I post something with a link to ping.fm, my twitter page posts it twice - once with a "ping.fm" link and once with a "lnk. ..." link that takes me to the myspace page. Facebook doesn't post at all (a separate issue), but when i post it manually to facebook, it also shows up on my twitter as a "facebook" link, presumably through the ping.fm (which is the only way the networks are linked together). I also notice that sometimes the myspace page shows multiple postings.