I'm starting to hear irritating creaking sounds in my drivetrain. I replaced my sprocket, the previous looked bent. The sound was gone for a short time. I replaced my freewheel hub to a cassette and then I started to hear the sound again. It appears my sprocket may be bent again. The one thing I missed was the chain. It looks to have tight spots and loose spots when I rotate the crank. Is this the sign for a new chain? Thanks in advance.

there was a very involved thread on this subject over the winter, seems like it related to profile crank spacers.

I am running Primo Powerbites/sealed BB/Standard sprocket on my daily rider.
After a lot of jumping my cranks developed a creak.
After having the whole system torn down, alignments checked and thoroughly regreased, the creak persists.

I am sure that the sealed bearings are slightly damaged but I have decided to live with it for the riding season.

What you have there is crank squeak.
Either the arms or the spindle are most likely worn.
This is predominant on square drive cranks, when they loosen up over a period of time and you ride on them you will sort of 'oval out' the crank arms where they attach to the spindle.
What cranks are you running?
When you replaced the sprocket did you remove then retighten the crank arm?
That may have cinched things up and got rid of the creak temporarily.
Was the sprocket actually bent? Did you check it on a flat surface after removing?
Check the chainwheel bolts for tightness and looseness on the crank arm attaching to the spindle.
Sometimes there is not enough perceptible play, but enough to make it squeak.
Try some Loctite. It may work, or it may work for a short time.
Probably creak is coming from the crank arm.

Yup, probably the crank arm. Throw some grease in the spline and tighten that bad boy down.

...and don't tighten the pinchbolts too tight before you tighten the spindle bolts. alternate the tightening a little at a time starting with the pinchbolts. along with generous ammount of grease and correct ammount of spacers, thats best you can do to avoid squeaks in that area.