Agree with wildulmer. It’s the price of providing good service. Especially if the product has history. But moreso because you want to provide the best service you can.

Think of it another way. You said you don’t want to keep one on the truck, but it is no problem for you to do two truck rolls to accomplish a repair. How much is that costing you? What if you just had one spare, and every failure was a single truck roll and then you were done? You are money ahead.

I keep a few URC remotes on my truck, so an issue is done with one truck roll, and the client has no additional downtime. Although Sonos failures are very rare, I did replace a Connect on Saturday again, with a single truck roll.

I believe you need to rethink your position.