OK to Use Both Balanced and RCA Inputs?

On a power amp, tube or solid state, which has both Balanced and RCA inputs, is it OK to connect, say, a turntable (via a preamp) to the Balanced input and (at the same time) a CD player to the RCA inputs? Naturally I would play only one at a time, but does having cable plugs in both inputs present any problem for the amp? I am thinking in particular of the Audio Research VS115. Thanks.
Looking at a photo of the rear panel of the VS115, on page 2 of this document, a jumper is indicated as being required on the XLR connectors (presumably between the inverted input signal on XLR pin 3 and ground on pin 1) when the RCA inputs are used. The significance of that is it indicates that the RCA and XLR inputs are not independent of each other, with the RCA input presumably being connected internally to the non-inverted input on XLR pin 2. It would therefore be undesirable sonically (and possibly even harmful to the preamp or CDP) to connect both at the same time. See this thread.

-- Al
Thanks, Al, for the precise answer and the very relevant link.