TPS92512 High Pitched Noise

This is common and depends on component selection. The main culprits are ceramic capacitors and/or the inductor. Both can buzz audibly depending. The input capacitor is usually the culprit in PWM dimming noise and often it is just because it is undersized (I generally use 4x to 5x the capacitance when PWM dimming as I would otherwise need). But even if you have enough ceramic caps are notorious noise generators. Often if you just change physical characteristics it is enough (say swap one 1210 case size cap for two 1206 sized caps). Or you can use tantalum, or aluminum electrolytics, or low audible noise ceramics. But it could be the output cap as well if you are using one. Inductors can do this as well though they do so less often. Again changing it out for a different size or technology (shielded vs unshielded for example) can often take care of it. But make sure you are not close to its saturation current rating when PWM dimming or it could get much worse. Sometimes that is the only issue is the current rating is too low. In some rare cases the only option is to find the least offensive frequency and/or pot the board to deaden the noise. So you will need to check your inductor rating and if it is fine you will need to pinpoint whether it is still the inductor or the caps and then experiment with the offending component.