The invention relates to a portable device, such as a mobile station. Furthermore, the invention relates to a method of providing a user with information on the operation of the portable device. In the device, such a tone is produced that, due to a tone feature, can be distinguished from background noise. This feature can be tone frequency, duration, volume or moment of time. The device can analyse background noise automatically, and based on this, it adjusts at least one feature of the tone automatically such that the tone can be distinguished from background noise, and the background noise does not mask out the tone. Alternatively, the user himself can adjust the tone frequency or duration in a desired way so that it would be distinguished from background noise more clearly. The method comprises the steps of: (202) detecting an event that interests the user and concerns the operation of the device; (204) determining the volume of background noise in the usage environment of the device; (206) automatically adjusting at least one tone feature that can be sensed by hearing such that the tone is distinguished from background noise by a human hearing sense; (208) giving feedback on the operation of the device by using a tone. Alternatively, the method comprises the steps of (302) receiving a control affecting the tone frequency and/or duration and controlling the tone production from a user interface of the device; (306) adjusting the tone frequency and/or duration according to the control.