Your messenger version may be getting old. I had 5.6 and lost sound totally, couldn't see any room text except for my own. Find your version by going to Help at your messenger window at the top. Click there, it will show which version you have.
Next I suggest if you don't at least have Yahoo Messenger version 8.0, that you do an update.
There's a very useful website that addresses tons of Yahoo issues including how to uninstall/reinstall correctly. Be sure to read there: www.freecreed.com . They do have a "site search" feature..... type in there - Yahoo Messenger uninstall/reinstall, and follow instructions.
If you've recently switched to Windows Vista, you may lose voice chat. Freecreed can help with that also.
You can contact me about this if you need more advice.
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