Question:
My product has developed a fault or I have a question about a product which I have purchased or perhaps intend to purchase.  Who do I contact? 
 
Answer:
The HARMAN Luxury Audio Group includes the following brands: Arcam, JBL Synthesis, Lexicon, Mark Levinson and Revel.  The HARMAN Luxury Audio Group web site can be found here:  https://www.harmanluxuryaudio.com/ 
These brands comprise Hi-Fi and home theater products.  These products are not supported by HARMAN  Professional or HARMAN Consumer divisions.  Each brand has a web site which contains product and contact information for technical support. 
Arcam
 https://www.arcam.co.uk/
JBL Synthesis
 https://www.jblsynthesis.com/
 Includes high-end JBL home products: L100 Classic, L82 Classic, SA750, L75ms, 4309, 4305P, 4312G, 4349.
Lexicon
 https://www.lexicon.com/ 
Does not include Lexicon Professional products. 
Mark Levinson
 https://www.marklevinson.com/
Revel
 https://www.revelspeakers.com/