Distortion on E and C string when playing through the built in pick-up

[gingersong]

I am having trouble with distortion on my two lower frequency strings. At first I thought it is because of low batteries as my LED light indicated low batteries. I have replaced the batteries with different brands to try and eliminate the problem, but the LED light remains dim, and the distortion isn't clearing. My A and G string sound great through a sound system. Is the problem with the pick up?
I have a Kala KA-CE concert ukulele, with a UK-300TR built in pick up. CR2032 3v coin batteries

 

[jimavery]

If you turn the volume down on the ukulele, does that remove the distortion? If so then I guess those lower frequencies are driving your amp too hard. I'd perhaps try turning down the bass control on the uke to balance the strings out. It could be various other things, but try that first.

 

[bazuku]

A few things you can check;

Have a close look at the battery compartment. Look for corrosion of the metal contacts, ...although quality CR2032s are usually fairly leak proof . Offhand, I can't think of another reason that the “on indicator” does not light brightly with fresh batteries, but checking the cleanliness of the contacts is a place to start. If you have a VOM check the voltage of the replacement battery/batteries.
If your saddle or strings have been removed recently check to make sure the saddle is seating properly by pressing it downward with both thumbs (but don't overdo the pressure).
Most amps/preamps have some form of frequency filtering. In its simplest form this consists of a capacitor and resistor in parallel. If your built-in preamp has sliding frequency controls, they act to change the range of frequency by varying the applied resistance in these filters. There are other means of doing this but this is a common method. I am not familiar with that preamp, but it is possible that a component of the frequency control circuitry (typically a capacitor) has failed, or at least wandered off spec.
It is possible that both problems may have a single root cause, so fixing one may take care of the other.
If this is more than an isolated case, Google may shed some light on similar occurrences.

 

[gingersong]

Hi,

Bringing down the volume helped, but didnt eliminate the distortion completely. Thanks for the advice

 

[gingersong]

I think I'm going to find someone who can open it up and have a look at it. Thanks everyone