Lexus is200 stereo fault

[oman313]

Hi guys, really new to this so please bare with me. I've recently bought a Lexus is200 on a 51 plate and I cannot get any sound from the stereo. It switches on and I can find radio stations on the screen but there isn't any sound at all, not even interference. It accepts discs and tapes and still the same problem. I understand they have a built in amp.
Please could somebody advise me in any way on this matter. Thanks in advance.