It only took a few days with Sennheiser’s new Momentum True Wireless 4 earbuds for it to become plainly obvious that they’re a class above the company’s previous model in nearly every way. The design and overall sound signature haven’t undergone major changes. But through a number of under-the-hood tweaks and other more subtle improvements, Sennheiser has taken aim at the connection issues, software bugs, and quality control concerns that hindered the potential of its third-gen buds…