This keeps happening to me.
I am currently running V2.6.0-1.0.1 on my LV08
After 2 hours of uptime it suddenly drops hashing like this:
https://imgur.com/a/ouHjJImIt averaged 5Th/s using 600Mhz at 1205 mV averaging 24.5J/TH for nearly 2 hours and suddenly it drops to 3.1th/s
It did not overheat: 55C asic temp
I was pushing this same hardware with the original LuckyMiner OS to 650/1260 and it averaged 5.35Th/s
Any suggestions ?
Use additional cooling to bring the temperature down on both the ASICs and VRMs. The cooler you can get them the more efficiently they will run. My first LV08 is still cracked open with a 120mm PC fan on top of the heatsink. Otherwise, put a fan up against (or close to) the intake vent and you'll see the temps drop.
At 600MHz and 1.25v on the core of the ASICs, my LV08 power is showing 109 watts with the ASICs at 47c and the VRMs at 53c. Power at the wall is 129 watts.
1.200v is too low for the LV08 at 600MHz in my opinion...