My recommendation is to get an 0.1 uF Audyn TruCopper bypass cap to put across it before you consider a complete cap replacement.
Tweeter Capacitor
A question for experts,
On my tweeter Esotar T330d I currently have an in serial a Alumen Z cap of 6,8µF,To match with the quality of the tweeter I am hesitating between a Duelund CAST Cu or a Milflex KPCU 03,the Milflex Cap has the same level of quality as Duelund?