The DME has to repair the Medicare machine.I do already have a backup machine, an AS10 that I bought (LSAT) out of pocket, but if my DME supplied CPAP failed before the 5 year replacement time I would want it repaired or replaced so I still have two working CPAP's. I just wasn't sure who would bear the cost since I own it, whether it would be me, the DME, or billed back to Medicare/insurance.
The machine you bought from LSAT isn't covered for repairs by Medicare. And may not be covered by manufacturer's warranty.
I bought my machine from cpap.com. It is covered under the manufacturer's warranty, but my own dime after that. I still have my old machine which has "exceeded the maximum motor hours" as a backup. That one is kept in my "go box" in case of fire evacuation.