The 1250 is not a 'sealed' pot, per-se, but it IS soldered directly to the Flat Amp PC board. Shooting cleaner down the shaft will simply wash any lube off the sleeve bearing and hasten its demise.

To clean the 1250 volume pot, the front panel gets removed, the function switch assembly has its screws removed (to allow a little more slack in the wires), and the Flat Amp is then unscrewed from the front chassis, slid back, and flipped over for service. Then, the volume pot is desoldered from the board (a job for a pro, since several of the quite stout tabs have been bent over during assembly, and desoldering without destroying the foil traces is not a job for a novice) and the plastic dust shield removed from the top of the pot. There are two types of Alps pots used in the 1250...one will allow access to the internals simply by removing the plastic dust shield...the other will require 'very careful' removal of the two long screws holding the pot together and carefully pulling the sections apart 'just enough' to allow the straw from the DeOxit cleaner to be aimed at its innards. Then you get to put it all back together again.

Someone is sure to jump in and tell you to drill holes in the pot to shoot cleaner in. I've always felt that this is a shortcut to a sure-fire way to turn the receiver into a doorstop while you spend the next 6 months looking for a replacement volume pot.