Mesa Mark 3 preamp tube heater voltage

[sixstring63]

Should I be getting the full 6 volts to the heater pins ? I get 3.12 VDC to pins 4 and 5 to pin 9 on V1 and -1.6 from pins 4+5 to ground and all other tubes are 3.2 VAC on pins 4 and 5 to ground. The heaters do not seem to be getting enough voltage to me.The tap from the PT is 6.4 V across both leads that also run to the power tubes which seem fine. I'm kinda running out of ideas. The voltage to my Ch. 2 foot switch is only 3.2 V and to the Lead foot switch with it is around 13 V and a big difference in LED brightness I've been told that these voltages come from the same supply as the heaters , I can not find where I'm losing half the voltage. Mike