I am having a serious issue with my Galaxy S4. The lock screen sound changes and I can't figure out why. I have reset my phone back to factory twice and at first it seems to have fixed the problem, then after about 30 min. to an hour it has changed. It also has lock me out of the lock screen effect under the settings. What can I do to fix this? Please help me I am truly aggravated by this. Thank you so much!!