You can see some options whenever you attempt to write a post. Use the "Media" option located to the right of the "Smilies" & "Images" options. Copy & paste your URL in the pop-up and you're good to go.
Soundcloud is what I see used here the most. That's probably your best bet, although many sites are supported (shown in the Media option).
Hopefully your crashing issue is rare. If it happens too often, try to pinpoint what might be causing the problem, or post a thread in support if you need more help. Be sure to back-up your projects to an external storage, in addition to what you have on your hard drive to avoid lost progress and frustration.