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How long have you had your L1 system?
Under normal circumstances, there should not be a strong burnt electrical smell. When the unit is new, there may be some off-gassing when the unit is new.
I can't speak specifically for about the SKB case. However, I have found some cases have some off-gassing when new. I would leave the case open outdoors for a day to air it out.
If you've run the L1 system for more than a few hours of operation and you experience a strong burnt electrical smell, please call Bose Support.
Bose® Product & Technical Support at (877) 335-2673
(U.S. and Canada only)
Monday-Friday: 9:00 AM - 9:00 PM ET