Short expression to convey "but consider the source"

Is there a short phrase (one to three words), Latin or otherwise, that conveys "but consider the source"?

For example, "I heard that pigs fly on television (your phrase here)."

I'm thinking perhaps a phrase that begins with the Latin word "caveat".

Solution 1:

You are probably thinking of caveat emptor, let the buyer beware.

Merriam-Webster

This is reported as new Latin, dating back to the 16th century.

While it literally refers to purchases, it often is used more generally to mean, be wary.

Solution 2:

You can also use the figurative phrase "take it with a grain of salt," if you adjust the original sentence slightly:

"I heard that pigs fly, but the report was on television, so take it with a grain of salt."

The idiom is defined in Christine Ammer, The American Heritage Dictionary of Idioms (1997) as follows:

with a grain of salt Also, with a pinch of salt. Skeptically, with reservations. For example, I always take Sandy's stories about illnesses with a grain of salt—she tends to exaggerate. This expression is a translation of the Latin cum grano salis, which Pliny used in describing Pompey's discovery of an antidote for poison (to be taken with a grain of salt). It was soon adopted by English writers.