For DIY repair enthusiasts: Respect the high voltage. A properly functioning CLA-2A is a thing of beauty–silky compression with absolute silence when idle. Eliminating that crack returns your unit to its intended glory.
However, with vintage-inspired analog gear comes vintage-inspired analog problems. Among the most reported and concerning hardware faults in the CLA-2A hardware unit is a phenomenon known colloquially as the Cla-2a Compressor Crack
For studio owners: Budget for a spare T4B cell. It’s the equivalent of spare strings for a guitarist; eventually, you will need it. For DIY repair enthusiasts: Respect the high voltage