Continue unchanging message, penning discrimination and slurs (8)

I haven't cracked this one yet — but the brilliant team at Times for the Times have:

BE (continue unchanging) SMS (message) around (penning) EAR (discrimination) These definitions stretched my sanity. But ‘ear’ does mean ‘the faculty of distinguishing sounds’, and ‘be’ does mean to continue without change. It’s just… sigh. Another clue that took ages.