Topic: outputs vulnerable when shorts not detectable?

I am using my headphones through an extension cable. Will any long-term degradation be caused to the output circuits when plugging into the extension please? (Because of the short circuit which happens when plugging a jack plug, and noting that the DAC's socket will not be able to recognise the plugging into the extension socket.)

For example, do I need to ensure that there is no audio, in order to completely avoid any long-term damage?