@KMan I’m using the Roon app on my Iphone 7 (iOS 11.2.1) with Cipher V2 cable and iSine 20s.
I was initially using the Fixed Volume setting in Roon and controlling volune through the Iphone buttons or the Cipher buttons.
I then tried the DSP volume on Roon and set the Iphone volume to max. I assume this means that Iphone/Cipher does no volume processing and passes the signal it gets from Roon. I can adjust the volume through Roon now. The sound does change and the bass clarity has improved. The sound is also brighter (more transparent?) and a bit pushed back. These are my initial impressions and i will listen a bit more to confirm.
Is this the best way to get the most out of the Cipher-Iphone-Roon setup ? Since two volume control options are there, please do confirm which is the best from a signal integrity (bit perfect) point of view, if indeed there is one.