Although many users are likely focused mostly on HD videos these days, Apple has still been taking steps recently to increase the quality of the SD video content in the iTunes Store, pushing the envelope beyond what older traditional iPods can handle.
If you’re still using an iPod classic or iPod nano for storing and watching videos, you may start running into an error message that “high-quality SD video is not compatible with this iPod” when you try to sync or transfer your videos.
If you encounter this, the fix is relatively simple: just go into your iTunes Store preferences and uncheck the option to “Download high-quality SD videos.” You’ll need to delete the problematic videos and then download them again from your iTunes Store Purchases section to get them in the slightly lower, iPod-compatible quality, at which point you should be able to sync them onto your iPod classic or iPod nano without any problems.
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