UR24C - Lower output level on Left channel than Right channel for PHONES and MAIN output

Hi! just as the title claims, I just purchased a UR24C unit and it sounds weird from my headphones. I did some tests and find out that MAIN and PHONES output has different output levels on two channels(Left is about 10% lower than Right). I do NOT have windows sound balance changed and it does the same on my Macbook as well. After contacting my online retail store I purchased this unit from, they shipped me a new one as an exchange. but unfortunately, the new one still performs the same - Left is 5% or 6% lower than Right. Are all UR24C units designed to be like this or It’s my online retail store giving out bad units? does anyone else face these problems or never have found out that the output levels are different on the Left and Right channels?

If the units have a design flaw regarding output levels you would find millions of posts about that.