Quantum Corp down after posting fall in quarterly revenue

** Shares of Quantum Corp QMCO.O down 16.8% at $7.13 after the bell

** QMCO reports Q1 revenue of $64.3 million vs $72.3 million in the year-ago period

** Posts Q1 adj. loss per share of $1.58 vs loss of $1.59 a year ago

** QMCO expects Q2 revenue of $61 million, plus or minus $2 million; adj. loss of 26 cents per share, plus or minus 10 cents

** As of Wednesday's close, QMCO has fallen 84% YTD