Specially considering you don't need to flash it into the controller's nand, just boot it from the sd card by moving a jumper. Don't like it? Take out the card and move the jumper back. Nothing happened.
This point has been discussed a few times before, to me , that is a lot of work when compared to flashing a firmware from bitmain in 10 seconds using only a web browser, now this "a lot of work" is subjective indeed, and depends on a lot of factors, the most important part is not being able to physically access your miner, I am still using bitmain firmware simply because
1-it does what it suppose to.
2-requires no effort.
3-could be flashed over the internet with ease.
So until I can flash braiins' with the same efforts ,I am going to sadly stick with Bitmain's version.
Lower speeds (in mhz), or increase voltage. Lowering the speed is safer, you should only try messing with voltages under 9v, else lower those mhz.
it depends really, i had some hash board that needed a very low frequency to run stable, the only way to have them run at a moderate frequency was increasing the voltage, and giving the fact that those will die soon anyway, plus I needed to ROI asap i focused more on increasing the voltage until there was no room then I started to lower the frequency, but everyone and every board is different.