Twenty years back Theta DS Pro Gen V DAC only got its chops after powered up for 48 hours. Unplug it for a minute and you had to start all over. Reportedly the Yggdrasil (same designer) has the same sort of behaviour. My Classe Audio preamplifier had no power switch. The Classe Audio power amp did better after warmed up for 20-30 minutes, but could be switched off and back on without penalty. ...So I keep the full system on all the time unless I'm going to be away for a few days.
Bruce
Theories are not so much answers as questions, to be supported or undermined by experience & testing.
Source: Audiolab 6000CDT > Calyx 24/192 DAC
Amplification: Pass-design B1rev2 pre-amplifier > Neurochrome Modulus 686.
Loudspeakers: Proac Response 1SC
Cables/stands: spkr: MIT MH-750 biwire; IC: HT Truthlink; Target stands, sand-filled; Excel Cat6A 23AWG UFTP & 1attack.de Cat.7 SFTP.
Other: Balanced AC transformer to hydra mains distr; Bass traps & Acoustic panels; Isolation: Inner tube & roller bearings; 3xZyxel ES104A switches in series w/Vreg upgrades.