Why won't my iPhone play a particular song or video? Why isn't a song or video visible? Why won't my iPhone play some songs and videos that will play on my Mac or PC?

If your iPhone won't play a particular song or video, or a music or video file won't show up in your iPhone, but these songs play without a problem in iTunes or other applications on your Mac or PC the most likely cause is that the song is in a format that is not supported by the iPhone.

You will need to re-rip the content from CD or DVD, re-download the songs or videos in a compatible format, or convert the songs or videos into a format that the iPhone can play.

EveryiPhone.com lists the audio and video file formats that each iPhone supports on the specs page for each model. However, these formats also are provided below for your convenience.

Supported Audio Formats

• AAC (8 to 320 Kbps)
• Protected AAC (from iTunes Store)
• HE-AAC
• MP3 (8 to 320 Kbps)
• MP3 VBR
• Audible (formats 2, 3, 4, Audible Enhanced Audio, AAX, and AAX+)
• Apple Lossless
• AIFF
• WAV

Other audio formats, like Ogg Vorbis, are not supported.

Supported Video Formats

• H.264 video up to 1080p, 60 frames per second, High Profile level 4.2 with AAC-LC audio up to 160 Kbps, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats.
• MPEG-4 video up to 2.5 Mbps, 640 by 480 pixels, 30 frames per second, Simple Profile with AAC-LC audio up to 160 Kbps per channel, 48kHz, stereo audio in .m4v, .mp4, and .mov file formats.
• Motion JPEG (M-JPEG) up to 35 Mbps, 1280 by 720 pixels, 30 frames per second, audio in ulaw, PCM stereo audio in .avi file format.

iPhone models that run iOS 7 support these file formats. File formats supported by older iPhone models may vary slightly.

Why does my iPhone "hang", "freeze", or skip in the middle of some songs or video clips?

If your iPhone "hangs" or "freezes" in the middle of some songs this is most likely due to a problem with the particular song file -- it could be corrupted, for instance -- or general data corruption on the iPhone.

First, try to repeat the problem and see if it is consistent with a particular song or video clip. If it only occurs with a particular song or video, the problem likely is only with the single file and it should be deleted or replaced. Odds are good that deleting the single problem file will solve the problem.

However, if the problem occurs with multiple files from different sources (ones that are not ripped from the same CD or downloaded from the same website), or you can not determine a particular pattern for the problem, try restarting the iPhone and see if that resolves the problem. If it does not, try resetting it.

If neither restarting nor resetting the iPhone solves the problem, try Apple's general recommendation to update its software to the latest version in iTunes and as a method of last resort, try restoring the iPhone. Note that restoring the iPhone will delete everything on it. Please be absolutely sure that you have the latest version of your files backed up before restoring your iPhone.

If problems still continue, which is unlikely, but nevertheless possible, you may have a hardware problem and repair may be needed.