The feel of my bass constantly changes

[Eric Hochberg]

I love the sound of my bass but I never know how it's going to feel. Sometimes nice and loose, and sometimes very tight, like last night when I felt like I was pulling on coat hangers. I haven't determined a weather related pattern to it's instability and am wondering if something in it's construction could be contributing to this? It has a new fingerboard and is set up well.

Any ideas?