I purchased this item for the winter while the wood stove is burning. At first it worked fine then out of nowhere it started making this screaming squelching noise. It was so annoying that we returned and exchanged it for another. So far (two weeks) the second one has been working as it should, quietly.
Garmin Edge 520 Bicycle Computer: Strive for success in competitive cycling with this bicycle computer, which helps you set and achieve goals. The Edge 520 is compatible with select Varia bike radar and lights, ANT+ indoor training sensors and GPS GLONASS satellites for flexible operation.