Faulty dac amp and customer service not interested.
I bought an S9 pro balanced dac amp and after a few weeks the 2.5mm socket developed a fault where one channel would switch in and out. I contacted the customer service who were probably as uninterested as the guy working in the local McDonalds. The item came from Italy yet they wanted me to return it to China. Needless to say I haven’t bought anything else from them. Seems like they’re not interested once they have your money. Be aware.