My system comprises of Sonos Connect, Rega DAC R, Sugden A21SE Amplifier and Neat Iota Alpha Speakers, I changed over the mains cable to the Sonos Connect for an MCRU No. 27 mains cable, as fitted to my other equipment. The overall Improvement to the sound quality is very noticeable with increased dynamics and transparency of sound. Also on another matter, following recent upgrades to the Sonos OS, I lost the facility for using the variable sound output. As my amplifier's line input is a very sensitive at 110m and the line output of the Rega Dac is around 2.15V the volume control on my amplifier rarely exceeds the 9 0'Clock position. In order to balance the system out I installed a pair of Rothwell 10dB attenuators between the DAC and the Amplifier. This has increased the sensitivity of the volume control up to just beyond the 12 O'Clock mark without losing any detectable definition. Just to finish off, I am still purchasing new CD's and burning same to the Apple lossless format with iTunes. The Sonos app then catalogues then catalogues the iTunes folder. All of this works very well together.