Multi-touch touch-sensing devices and methods are described herein. The touch sensing devices can include multiple sense points, each of which can be stimulated with a plurality of periodic waveforms having different frequencies to measure a touch value at the sense point. Noise at one or more of the frequencies can interfere with this measurement. Therefore, various noise detection (and rejection) techniques are described. The noise detection techniques include two-clean-frequency noise detection, one-clean-frequency noise rejection, and combined two-clean-frequency/one-clean-frequency noise detection. Each of the noise detection techniques can include statistical analyses of the sample values obtained. The touch sensing methods and devices can be incorporated into interfaces for a variety of electronic devices such as a desktop, tablet, notebook, and handheld computers, personal digital assistants, media players, and mobile telephones.