Having a problem with my machine

hey , I have a chinese industrial embroidery machine 12 heads , 9 needles and the system is Dahao .

since couple of months I've had a strange problem with my machine , sometimes after starting to sew or even after the thread cuts and start working again , something is going wrong with the system , the machines turns off for less than a second and on again the screen shows Dahao ( which is usually shown after you turn on your machine ) the main motor doesn't stop at 100 so I place it on 100 to start again sometimes the problem happens again and sometimes it doesn't , the frame always moves out of it's last position so I have to fix that every time or ruin my whole 12 peaces .

I tried to check the main board replace it also , test the cables , the monitor replace it also , the main motor and it's supplier box I've tried alot and didn't know the reason of my problem .

can anyone help me with any info to solve my problem ?