🤯 Legacy Audio Calibre XD humming + no low ends & boxy sounding

I have recently purchased a pair of Legacy Audio Calibre XD from a friend, and upon wiring it using XLR straight to the DAC preamp, the sound shocked me with disappointments. I wonder if this is the Legacy’s house sound or that something is wrong with the pair?

Symptom: 

(1) left speaker emits audible hum on all drivers with only the IEC cord attached; unless a balanced XLR is plugged in. Right speakers are near silent when on. 

(2) when playing music via XLR the bass below ~60-80 Hz is almost absent—the front mid-bass driver barely moves while the top woofer carries vocal/mids. REW sweeps below (I don’t have the best measure mic). 


(3) I was expecting clarity, dynamics, and separations of instrument due to the Calibre being a 3-way speaker. But I found the sound to be sort of muddy and similar to a JBL with worn out drivers.... I now start to wonder if it’s just my sonic preference for highly resolved speakers or that something in my set up is wrong. 
 

Checks done: rocker switch is down (full-range). Source is a Topping D90 II Discreet running Pre-amp mode with 4V out and -25db level. Source runs fine with a BW 805 D3 + External Amp with full bass. 

Contacted Legacy service via email but haven’t heard back yet. I wonder if anyone had experience with Legacy Audio product line, particularly the XD line, who know what this is about? 🙏