Quote from the Pieps/BD press release:
"We have detected a malfunction in the electronics of a small number of devices. In this case, the device may not switch from transmit mode to search mode. All customers in possession of the devices listed below are therefore requested to check them using the following instructions or to contact our customer service."
Affected are:
PIEPS Micro BT Button
PIEPS Micro BT Race
PIEPS Micro BT Sensor
PIEPS POWDER BT
PIEPS PRO BT
PIEPS DSP PRO / SPORT
BLACK DIAMOND RECON
BLACK DIAMOND GUIDe
More information and more detailed instructions for checking the various devices can be found here.
Switching between search and transmission mode needs to be checked. It gives the impression that this is a problem that you as a user would notice anyway if, for example, you regularly carry out avalanche beacon checks at the start of the tour, but the description of the problem is not very detailed.