[jigglesniggle]

I have to agree with sangnoir. I don't want to provide free engineering services. I want a working product. If you are explicit about component compatibility and provide a troubleshooting checklist (all ways it must be plugged in and turned on) then you should assume there is an issue. You should also treat the boards as interchangeable; if a board comes back, you test it and it's good, ship it out again.

A family friend will help me troubleshoot my electronics. So, I have seen the other side of this: I get something which is completely nonfunctional and send it back to the manufacturer who claims it is functional, and tries to bill me for the shipping both ways. That's why if I can not get a working replacement in 2wk or so I just send it back for refund.

For a real example: Are you using very well made power supplies? Maybe your board's power filtering could be better, and customers notice because they buy the cheapest supply that meets their power requirements.

[tpearson-raptor]

All of the Raptor products use very high quality regulators and power filtering. The only cases of PSU-related damage or malfunction that I am aware of were as a result of a PSU operating way outside of specification (think 12V+ on a 5V rail) or a poorly made PSU exploding and catching on fire, with predictable consequences for the attached devices. Thankfully such incidents are rare, and have never happened with our prebuilt systems that use high quality PSUs.

In general we can diagnose and repair or replace the systems rapidly. This one case was an extreme outlier, and in the future we will just be authorizing RMA and replacement / repair.

[jigglesniggle]

Ok, that sounds good. The example was more just to be illustrative. But there is the (slight) possibility of harmonics on the power lines, etc. There are EDA suites that can do such signal analysis on your board but they are quite expensive. If you picked just the wrong values there could be a filter system which amplifies noise from a power supply.

The trick is to get your board manufacturer to eat the return cost. If you can buy testing, do so; usually it comes with some assurance that the boards work, and they either make new stock or remanufacture what you send back. If you can point to a comprehensive testing instructions that the customer would have performed it should not matter if you receive the board and it works for you, for some reason it did not work for the customer.