Several wks ago, ending a programed rec session it is jerking tape back and forth, all the lights flashing. Now, competely going off & I have to catch it trying to come back on to be able to press the power button & get it on so I can eject tape. Was keeping time until yesterday when the clock went blank. Still programmed to channels so I know the power was not off to cause a full reset of the machine. Is there an internal battery that has died after almost 20 years? Fixable??