I have an Ibanez SDGR 4 string bass which I have just put new strings on (same gauge strings). The sustain of the harmonics on the fifth and seventh fret on the G string is very short and "wobley" sounding. I have tried adjusting the bridge saddle and no luck thus far. Could this be an issue regarding the neck having to much stress or relief?

Any advice would be much appreciated.
Thank you.
Yes, it could be neck relief. The curvature of the neck is a critical factor in determining scale length, which in turn determines how your harmonics are going to ring out. Have a good guitar or bass tech check your bass neck for (a.) proper neck curvature, and (b.) make sure there is no twist to it - a common problem that is fixed with a truss rod tweak.
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