A pet peave of mine is cheap, crummy connectors. They are often difficult to install plus they frequently cause all sorts of tough to diagnose intermittent problems. Recently I came across some really high quality 1/8-inch (3.5mm) mono and stereo connectors from Neautrik/REAN. They are available from Mouser in the US and undoubtedly many other suppliers as well. Cheap connectors are often well less than a dollar. These are $1.50 or more but you build a cable with one once and it just keeps working. A wise investment in my mind.
The mono plug is P/N: NYS226BG. The stereo version is P/N: NYS231BG. These are the real deal. Black metal handles, gold plated contacts.