Acquity H Class QSM making odd noise in combination with h/w error


We have an Acquity H Class UPLC with the QSM (serial number A12QSM398A).  A few months ago one of the pumps started making an odd noise, similar to a squeak, every time it pumps.  It's really difficult to tell if it's coming from the primary or the accumulator. 

Today the instrument shut down with a h/w synchronization error.  Everything was reset and the line going from the pump to the transducer was loosened.  Staring back up with this line loose, the noise was greatly reduced and allowed the instrument to run normally. 

This line was replaced with a brand new line as well as the line that connects the primary to the check valve of the accumulator.  The noise is still present and pretty loud, like an annoying squeak every time it pumps.  It's almost as if there's still a clog somewhere and it's having difficulty pumping.  Loosening the line from the transducer of the primary helped with the noise.  That being said I'm not sure if that indicated a problem before or after the transducer.  I'm thinking just releasing the pressure would lower the noise wherever it was coming from.

I'm not sure if maybe there is some diagnostic test to help determine the issue?