Where's your tuner in relation to the power amp? You need the tuner as far away from the amps and CDP as possible, unless it's very heavily shielded (you didn't mention the brand).
CDPs and Class-D amps can spew a lot of RFI/EMI and tuners are the most likely to be negatively impacted. I see you're running balanced, which is critical in Class-D, but does you tuner allow balanced? Make sure that the antenna lead doesn't run too near the amp.
If the whole shebang is in a rack, then try to get the amps on the bottom and the tuner on top. Ayre tends to shield their stuff pretty heavily, so maybe the CDP won't interfere with the tuner too much, but putting the pre between the CDP and tuner would be good.
Once you solve all this, then leave it on all the time. (BTW, I love Class-D and ICEPower stuff, using Rowland myself).
Dave