Russian big muff low volume and "motorboting"

[GrooveChampion]

So I built the 1994 Russian Big Muff and there...issues. When ever I plug the thing into the powersupply and switch the amp on the volume is OK for the first second then it drops and starts making this "motorboting" sound, like the high volume sputter.

I reflowed and rechecked everything and I am at a loss. Are the 2n5089's an issue?

[GrooveChampion]

Silly me, the pedal was A-OK....turns out my battery powered amp ran out of juice....