High Frets E String Warble?

[3bc]

I have recently "downgraded" a bass. The new bass is still pretty nice and shouldn't have big issues. However, if I play say, a high A on the E string (17th fret), it almost sounds out of tune with itself. It's all warbly/vibrato-y sounding, almost like a really old piano sounds out of tune with itself. Or a sitting in front of a synthesizer and slightly detuning two oscillators.

Nothing else is ringing out, all other strings are fully muted.

Anyone know what I'm talking about, or how to go about fixing this?

 

[Jeff Scott]

I have recently "downgraded" a bass. The new bass is still pretty nice and shouldn't have big issues. However, if I play say, a high A on the E string (17th fret), it almost sounds out of tune with itself. It's all warbly/vibrato-y sounding, almost like a really old piano sounds out of tune with itself. Or a sitting in front of a synthesizer and slightly detuning two oscillators.

Nothing else is ringing out, all other strings are fully muted.

Anyone know what I'm talking about, or how to go about fixing this?

Lower your pickups.