My Samsung Galaxy S4 is still on Android 2.2.2 and I believe it may be causing some problems. When I search for Software Updates, it tells me I have the latest version. Is there a way to manually download it?
Do you mean you have 4.2.2?
It all depends on your carrier and what they decide to send out.
Try connecting to a PC with Samsung kies and try from there.
Head over to sammobile and search the latest firmware available for your device.
If there is nothing available for your device, then do a backup and factory reset. Should resolve some issues.