Inflated Music Size on iPhone when Syncing Frequently when I sync my iPhone to my iMac, the size bar will report that the amount of music on my phone is nearly double what it actually is (confirmed with a manual check). The phone will usually report that it is over capacity, but I can still copy applications and more music to it (as I should be able to). This doesn't happen on every sync, and sometimes when the sync is completed, it will shrink back down to the correct size. It's a major annoyance and makes it hard for me to see how much space I actually have used/free on my phone.
I have found that it is related to iTunes Match. If you turn off iTunes Match on the iPhone, the iPhone will no longer register as over capacity.