10W laser - power issues?

I’ve just added a 10W laser and am having some issues I think with the power. If you watch the video of the laser in action you’ll see that it regularly seems to stop and start as it crosses the picture. I’ve noted that the lcd screen updates itself at the same time as these motion issues, do you think it’s a software issue?
I’m powering the laser from a 12v 30A psu thats also powering the rest of the setup, the laser is controlled through pin 44. The laser only has the two power leads and a single lead for the ttl. Bought together from here - http://www.aliexpress.com/item/10W-laser-AS-5-10000MW-big-DIY-laser-engraving-machine-diy-marking-machine-diy-laser-engrave/32652153790.html
The laser can cut through 1mm card very well, I’m hoping it can cut through up to 3mm so I can make jigsaws. The large card was cut in just over 7 minutes.
Here is the video - https://www.youtube.com/embed/ec4ybdzuijc - ignore the cable ties and messy wiring, tidying that today!
Should I try the Laser on a separate psu? (it normally runs off a 12v 4a supply) If so, how can I join the two psu’s together so that the ttl lead still works?

Your going to need to adjust the accelerations. You will need to turn them up in the firmware. Pretty sure that is from the rapid stop and start everytime the laser turns on and off. I handle it by just slowing down my burn and turning down the laser instead of reflashing. If you decide to turn up the accel, you will want to raise up your material to keep the z axis at minimum length to keep it from resonating from high accel to keep your etching looking nice.

I don’t know anything about that laser but looks like you might need to be careful it has a 50% duty cycle, and it seems a little fishy the ad says 10w the driver says 3W, and in the middle it says average 6W.

Thanks for that. Will try that today.
I think the main issue is that the laser needs to be controlled with pwm rather than ttl. The Chinese software has options for power (0-255), stable delay and time.
If anyone has any suggestions on how to write the code for this I will be eternally grateful! Being able to set those variables will give a lot more control over the laser.

I think Vicious is right on about the accel settings. The lines on the border of the image aren’t straight. You can see that the machine is resonating. I have this issue with vector engravings but never with the smooth sweeping motion in raster engravings. What software are you using and what is your feedrate?
Also, if you’re using Marlin then you are controlling the driver with 8 bit pwm(0-255) already.