Have you done a device refresh since the IOS update?
Let's try this:
1. Tap Phone icon.
2. Tap Key Pad if necessary.
3. Enter ##873283# then tap Call icon.
4. When Starting Service Update appears, tap OK.
5. When Service Update Complete appears, tap OK.
When Sprint displays in the top left corner, the update has completed. Power off, WAIT 5 minutes and back on.
It may be your facebook app if that's the only video that is blurry.