Shure sells an attachment that adds inline volume controls.
Oh I see what you're trying to do now. Disregard my post above. All you need is an inline volume control
This is the exact model that came with my Shure SE-535 and I notice no loss in sound quality.
I don't know of any way but a possible workaround is an in-line volume control. I have one of these and it's more convenient to adjust volume with than s/w controls for me:
https://www.amazon.com/gp/product/B001P5HL3S/ref=oh_aui_search_detailpage?ie=UTF8&psc=1
Have you considered using a volume control adapter? I have one of these -
Thanks, that one popped after I posted, there is something similar I found from Shure ( https://www.amazon.com/Shure-EAADPT-KIT-Adapter-Combines-Attachable/dp/B001P5HL3S/ref=sr_1_1?ie=UTF8&qid=1502962538&sr=8-1&keywords=shure+airplane )