You need to fix your Skype icon that members that add their Skype to their profile. As seen in this thread, Hi-Freqency Pool User!! The user rickydazla his Skype icon is broken, and makes the postbit look terrible.
The thing to do is go to AdminCp --> Settings --> Options --> Style & Language Settings --> Use SkypeWeb Graphics. Check what the setting is. If it is set to "Yes", change it to "No", and that should fix the issue. Make sure to refresh the thread page in order to see the changes.