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While WAPs can degrade over time, you are more likely to be hindered by outdated technology/protocols than the aged internal components. WiFi uses precise timing in order to send/receive signals to/from your devices, avoid collisions, and even triangulate your device's location (with newer WiFi 6 protocols) for more efficient transmission. It It is possible that the timing component, usually a crystal oscillator, can degrade over time due to an aging power adapter or a very RF (radio frequency) noisy environment. Nevertheless, it is likely outdated technology/protocols that are slowing down your connection and not the physical health of your WAP.
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