how to know if the avr is new or refurbished or returned by another customer

[sand87]

can i use any other centre speakers with my Polk S20 or wid i need to stick with polk S30 centres??

 

[sand87]

any yamaha rxv 685 users here.if yes then on the avr is the right wifi antenna connector slightly bent inwards instead of straight.the reason my antenna cms loose and tighting it is inpossible because the nuts on that connector stem is loose.is it like that