Mechanical switching like that does have a little pop as the switch is switching between the circuit and the output jack, whereas Boss and similar pedals have the buffer bypass and are silent, basically because the signal is always going through the circuit.
Bypasses vary, cheap ones can be poppy and/or can wear out rather quickly. Contact cleaner may help, but more than likely it is just the sound of that switch, unless it has gotten worse?
Even the highest quality of pedals can have switches that fail. I had a both a Darkglass B3K and 3Leaf Wonderlove that both needed their switches replacing, although i think that was due to the builder having a few teething issues with their soft touch relay bypass. Bloody lovely switch though