The Collaborative International Dictionary of English v.0.48:
Snuffle \Snuf"fle\, v. i. [imp. & p. p. Snuffled; p. pr. & vb.
n. Snuffling.] [Freq. of snuff, v.i.; akin to LG. snuffeln,
G. schn["u]ffeln, D. snuffeln, Dan. sn["o]vle. Cf.
To speak through the nose; to breathe through the nose when
it is obstructed, so as to make a broken sound.
One clad in purple
Eats, and recites some lamentable rhyme . . .
Snuffling at nose, and croaking in his throat.