free variation in pronunciation

[Frank Abate]

Lynne M asked:

>>
Are there
any other examples of absolutely free variants in lexical pronunciations?
By my definition of "absolutely free", they must be equally acceptable in
all semantic, social, (in)formal, stylistic (etc.) contexts for a single
speaker/speech community.
<<

I think the two prons of "envelope" qualify, with variation on the first
syllable between "EN" and "ON".

Unless someone out there sees a distinction in register?

Frank Abate