Left suitcase amp on overnight - disconnected from preamp

[Yaniv Brener]

Well, I did a dumb thing and left my suitcase amp on overnight with the 5-pin power amp cable disconnected. It might just be paranoia, but I feel like it now hums louder and the sound is 'crunchier'/more overdriven even at low volumes.

Does anyone know if this would cause damage to the amp due to not having an expected load on the input side? Am I just being paranoid?

[Tines&Reeds]

Yes you are.
The voltage regulators don't care if they don't have a load as well as the power amps audio inputs.