Default SD Card Problem

Anyone experiencing constant SD card unmounting with the latest firmware? Suddenly I'm having this today.
Past - Present Android Devices

Present Android Device: Sony Xperia Z Ultra - C6802 - 14.2.A.1.136 - Stock - Bootloader UL - Rooted
Backup Android Device: Sony Xperia C - C2305 - 16.0.B.2.13 - Stock - Rooted