LP vs SP tuning stability

[Gil]

Hi all,

I own a Little Phatty Stage II for half a year now,
love it so much that I went yersterday and bought a Slim Phatty to go along with it.

Yesterday I powered them both up at the same time, and set both on autotune (without playing so as not to interrupt the process).
First thing I noticed is that the SP took a lot longer to reach 60.00. Not a big deal though.
Problem is, with my LP, once autotune reaches 60.00, OCS1 stays rock solid, drifting only by a cent or two max.
The SP's OCS1, however, kept drifting up to 20 cents too sharp, and I had to keep going back to autotune to let it tune itself.
Only after around an hour did the tuning become as stable as my LP was after 2 minutes.

Is this normal? Temperature is warm and steady in my room, no fluctuations.
I did notice that the SP runs a lot warmer than the LP, maybe that's the reason?
I powered it up today again and had the same issue. I'm now running a full calibration though I doubt it'll help.

I guess what I'd like to know is if this is normal behaviour for the SP, and if it is known to be less stable than the LP.
Thanks,
Gil

[FutureProof]

From my limited experience that seems to be the case (ie slim not as stable or taking longer to get stable). Perhaps to do with the larger enclosure of the LP?

[Gil]

I suppose that's the reason. Thanks!