How many seconds can Apple's ringtone be compressed?

The length of ringtone is limited to 40 seconds to prevent waste of resources. When the call comes in, the bell is just a reminder. When the call time reaches a certain level, the operator will stop the call and enter the no-call answering mode. At this time, no matter how long the ringtone music is, it is a waste of resources. So it is necessary to compress the playing time of ringtones. Apple stipulates that the ringtone length in the system is 40 seconds, and any ringtone that exceeds the time length will be used.

The ring length of 40 seconds is agreed by the system. As long as the data of the system is modified, the allowable time of ringtone playing can be changed, or there is no limit on ringtone playing time. Of course, the system files must be modified.