Interesting idea. Will try that. This is certainly quite frustrating trying to fix. Perhaps not bothering is the best option
I've looked at huff-puff before. Definitely an option for this so might go down that route. I want this to be very stable as I've got a very narrow audio bandwidth filter on the other end of the receiver for CW reception so it's frustrating when it drifts out of the pass band. Grr!
I have looked at a proper DDS VFO. In fact I built a Si570 one from scratch but the thing drains 80mA of current continuously when receiving versus 1mA for this!