I encountered it before, but thought it was a bad recording. Now I heard it again and this problem happens at all playing tracks;
I heard a cracking sound through both speakers after listening to the music for a while. At first the music is sounding fine, but after (I think) 20 minutes of listening a “cracking sound’ appears and the sound becomes very bad (not elac worthy). I am using the air-x base which transmittes the sound wireless to my 407 air-x speakers. Unfortunately the speakers are just out of warranty for the amplifier part. Does anyone regognise these problems and knows the cause of this problem?