Remap headphone buttons I listen to audible for multiple hours everyday, im wondering if anyone knows of any way/app that will let me remap my earphone buttons to something more useful than play/pause or volume up/down, the amount of times I need to grab my phone out my pocket to click the 30sec rewind is quite inconvenient
I have the same problem, wired headset control worked nice with Podcast Addict (after some minor tweaking in podcast addict settings), but rewind/forward(i.e. prev/next) = double tap/triple tap, on the play button, DID not work with Audible.

A partial solution I have, just tried recently (August 2019): 


install "button mapper" app (the app has nasty privileges, a short inconclusive google search suggests those privileges apparently are required to allow the app to do what is intended to do - but please investigate yourself)
in the app, in Headset Button section assign "double tap" to  "rewind" function.


and more or less it works with Audible. The shortcomings: 

A) IS NOT WORKING WHEN  SCREEN IS OFF (perhaps is working with screen off on rooted devices). 

B) when "double tap" it jump in the Audible the required amount of seconds back but it also pause the playback (so the action is: play-listen, when I want to jump back: double tap, then again a single tap to resume playback)

C) it messed my controls with Podcast Addict, when mapper is enabled, so I have to switch the mapper off to use with podcast, switch on for Audible, (perhaps a further tweak in Podcast addict settings will fix that for me)

For working with screen off, there is a link suggesting some solution, I have not tried this: https://elementalx.org/button-mapper/screenoff-noroot/

Other option perhaps to investigate is a Tasker app.

If any one has an update or know if Tasker can do the job better, please share.