what would cause a shift change like this

Check your wiring, trim pots, belt tension (if its too tight it will skip, if its too loose the belt will jump teeth).

make sure your trim pots aren’t set to high(steppers over heating will cause lost steps), steps per mm are the same for x and y eg x = 80, y = 80 if one is offset it will cause wired effects (oblong parts etc)

As said before check your acceleration, and one more item that some over look, make sure your build area dimensions are the same in your software as in your firmware this will cause weird effects as well.

Just took a closer look at your photo, when I have this issue (prints fine for like 10 layers the makes stairs all over your print area) it’s almost always the belt tension, either too tight or too loose.

I’d agree about turning up the current. If you’re running without heatsinks and the driver chips aren’t even uncomfortable to touch while they are running, you may be very close to not having enough torque, which can easily turn into lost steps.

Sometimes when you’re close to a limit like that the machine will run fine except in very specific circumstances where conditions are just right.

Is the noise more like a hiss, or a squeal? Depending on what you are using for drivers you might be able to adjust the switching frequency to silence them.

When it was printing im sure I heard my motors stop or vibrate like. It sounds like a squeal to me. Ive upped the current a little and made some heat sinks to put on it. The squealing only seems to happen when I manually move the motors and at the very start of a print after it starts going it seems to get quiter

Mm mm could be picking up a radio station ( no joke) I have a video of my y axis stepper playing a radio station, ill have to find the link.

Found it http://youtu.be/W2r8HCY6Ers

Unplug your Y motor and move the axis by hand. Is the squealing still happening? Either way can you locate where the squealing is coming from?

Jeremy G thats crazy it did that. I don’t believe that I’m having that problem. It doesn’t make it when the the motor is unplugged. So far I’m thinking that i had my current to low cuz its not doing it anymore

@Chad_Nuxoll high pitch whining of the motors is completely normal behavior.

@Jeremy_G_WeisTek_Eng That’s so crazy… Can you tune it to different stations by moving the axis it’s connected to, or are you stuck with just the one station?

I tried to tune into different stations, only thin I could accomplish was making the station come in better (touching the stepper helped with clarity as well) my friend an I decided that with the blown stepper driver the stepper was hitting just the right resonate frequency of a nearby radio tower and this picking up the station.

I seriously thought someone was out side my office window for a min until I honed I on it :smiley:

… I hate my phones auto correct…

Yes Ive calibrated the Z So far after turning up the current on my motors I haven’t had this problem. Thanks everyone again for the help