BT will certainly want to see that device and investigate. They will take it seriously and the product development teams include people to investigate failures such as that.
Over the years there have been failures in BT equipment, not very often but it can happen. The will take it very seriously.
Advise your friend NOT to let the Technician take it with him as it will probably end up being dumped, but to hold on to it and make sure it gets to the right people.
M H C
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