I would second or third the recommendation to send your 20.5's back to the Levinson repair department, if you think that they might need attention.
I have, on occasion, had to send both a cd transport as well as my 332 amp(that I shorted out and blew the right channel) back to the guys at Levinson, or the Harmon Group, their parent company.
There are guys in the department that have been there for many years.
There is probably a flat rate for replacing or upgrading the amps.
Trust me, they will do a great job.
But, "if it ain't broke....."
I have, on occasion, had to send both a cd transport as well as my 332 amp(that I shorted out and blew the right channel) back to the guys at Levinson, or the Harmon Group, their parent company.
There are guys in the department that have been there for many years.
There is probably a flat rate for replacing or upgrading the amps.
Trust me, they will do a great job.
But, "if it ain't broke....."