Universal Audio 4-710D For Sale. We bought this from one of our customers who never used it. Regardless, quality control is of the utmost importance to us, so we opened it up and tested it out. What we found was that several of the pots crackled. Our tech said at least one would likely need replacement, but he also said it may take a while to disassemble it and then figure out and order whatever replacement part/s were needed. Swamped with vintage synth repairs, and realizing UA can disassemble these and replace parts much quicker, we sent the unit back to UA to resolve the issues and give it a full test. We got it back from them, factory-tested and approved, and now it's ready to move on to its next home. Original manual and power cords included.