Pro Art Creator board - Flashing Red/Amber LEDS each morning until I clear CMOS?

Hi Guys,
I have a really strange issue with my Asus Pro Art Creator board and would welcome any comments or suggestions. The board worked fine initially. Then, one morning it failed to boot and the Red (CPU) and Amber (RAM) LED warning lights began to flash alternately. I checked the CPU and RAM and reseated them followed by clearing the CMOS. I then left the computer alone for a couple of hours, after which it posted as normal. After that I was able to turn the computer on and off all day long with no issues.

The following morning the problem was back and I had to go through the clear CMOS process and wait all over again. A couple of days later I replaced both the CPU and RAM with new QVL approved components to make sure they were not at fault. The computer booted and worked for 2 days before the issue again reappeared. I cannot understand how leaving the computer off overnight can result in the need to clear the CMOS each day?

Asus has checked the board and claim there is nothing wrong with it and said it must be the CPU or RAM? How can it be? once it boots it works fine - until the following morning, bearing in mind I have installed two CPU's and two different sets of RAM both of which comply with the ASUS QVL list. I also tested the original CPU and RAM in a Gigabyte board with no issues.

Anyone have any thoughts or suggestions on what to check?