Plantronics Sees Q3 Adj. EPS $0.01-$0.31, Sales $383M-$423M vs $511.9M Est., Sees FY20 Adj. EPS $2.94-$3.74, Sales $1.72B-$1.81B vs $1.95B Est.; Co. 'expects to reduce channel inventory by approximately $65 million by reducing sales to channel partners'