Hum when connecting guitar to UR44

I experience a strong hum when I connect my fender stratocaster deluxe to any input in my new UR44. That hum doesn’t appear when I connect my guitar to any other device in my homу studio (guitar combo, mixer or guitar processor). Фе the same time that hum doesn’t appear when I connect to UR44 any other device.

Did anyone experience the same?

Does the hum vary when you move the guitar around?
Could be the SC pickups picking up interference from a nearby source - Monitor or TV, Fluorescent lights, transformer etc.

Yes the hum does vary a little but what makes me worry is that it doesn’t appear at all on another equipment. I think that can be some issue with compability between guitar, guitar cord and UR 44. I just don’t understand what can it be

All siinglecoil pickups hum - that is their nature. Typical for Strats, Jazz Basses.That is why humbuckers were developed.
Have you switched the Hi-Z on the input? Maybe you should try to connect a guitar with humbackers just to check if there is a difference? Change the cable - some may very noisy ( last Sunday I have wasted two hours looking for a hum in the system and in the end it was perfectly new Monster microphone cable). Only than, I would say it is the audio interface - but even if everything is fine Strat will hum in some pick-up positions: should be OK if two of them are on at the same time