Q I have several table radios that have developed a problem with the volume-control knob. Touching the dial causes static noise along with difficulty in adjusting volume. What causes this problem, and is there an easy fix?

A That problem is common with older electronics and is caused by dust in the volume-control pot.

Electrical contact cleaner spray usually does the trick. Just open the cover of the radio (be careful that the radio has been unplugged for a while), and spray the contact cleaner into the pot behind the volume- control knob. Work it in by twisting the dial.

While you are cleaning the volume control, be sure to clean any other rotary dials such as the tuner and the source selector or balance controls if it is a receiver. Dust in any of these can cause problems.

If you don't want to try this, a professional cleaning at a local electronics repair shop shouldn't cost much.

Kodak camera still good buyQ Do you still recommend the Kodak Z990 EasyShare Max superzoom camera now that Kodak is getting out of the camera business?

A I still consider the EasyShare Max a good camera and a good buy at current prices, which hover around $200. I wouldn't recommend spending more than $225 to get one, though. The camera has a feature set that is unique, and I have thought about snagging one while I still can.

Although Kodak is honoring warranties on its existing digital cameras, you might want to consider an extended warranty. Another superzoom camera under $200 worth considering is the Olympus SZ-12. It lacks the Kodak's viewfinder but is compact.

Any receiver will doQ I have an old Pioneer Elite receiver that has been great for my large DVD library, which has AC-3 Dolby Digital 5.1 sound. I now have a small bunch of Blu-ray discs but can't take advantage of the Dolby TrueHD sound through my receiver, and most Blu-ray discs don't have an AC-3 5.1 audio option. The receivers I have seen that can decode TrueHD don't process AC-3 5.1. Is there a receiver that can do both?

A AC-3 Dolby Digital and Dolby Digital are the same thing. When Dolby first introduced the format, it was called AC-3, then AC-3 Dolby Digital, and now simply Dolby Digital.

All Blu-ray discs with Dolby TrueHD also have a Dolby Digital track, because, like you, not everyone has a receiver that can process Dolby TrueHD. Dolby Digital on Blu-ray is recorded at a higher bit rate (more information) than DVD Dolby Digital, so it sounds noticeably better.

You can get whatever receiver you want, because all of the ones that decode TrueHD also handle Dolby Digital. All HDTV broadcasts have Dolby Digital sound, so it is imperative that receivers can decode it.

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