Model U124D/. One hand held power lock works, one does not. One lav power lock works, one does not. Is it something I am doing?
The power lock feature on every U series transmitter works the same. Here is a test to try on each transmitter:
1. Cancel the Power On Lock function by removing the batteries. Then replace the batteries.
2. Power on the transmitter.
3. Press and hold the SET button, then press and hold the MODE button.
4. Hold both buttons down until "PoL" appears in the LCD display. The transmitter is now locked on.
If you cannot do this on each transmitter, contact Shure Service at 800-516-2525 to obtain details on returning the defective transmitter for repair.