All 7-Series recorders, including the 788T, operate from removable, rechargeable Li-ion batteries. On power up, the 788T briefly draws more current from these Li-ion batteries than during continuous operation. This "in-rush" current is caused by the numerous circuits initially being energized.
Reports from the field indicate that some L-Mount Li-ion batteries available in the market are susceptible to their current protection circuit kicking in when initially powering the 788T. With these cells the 788T will not power up, however, once powered (from external DC), the units operate normally from these cells. Batteries susceptible to this condition have very fast current protection circuits which are tripped by the initial 788T power-on current surge.
In rare instances this condition has been observed with the factory-supplied battery. If you experience this condition with the battery supplied with your 788T, please contact the Sound Devices Support Staff.