Old setup was as follows: Lenovo W520 connected to TV using a passive DP to HDMI adapter. Audio was fed from the TV to the Harman Kardon receiver with digital coax. Audio worked fine, no delays. Then ...

Testing FM receivers is not that much different than testing other pieces of audio equipment. Appropriate tests include the big six: level, frequency response, THD+N, phase, interchannel crosstalk, ...

I have an older Panasonic TC P50ST30 (release review/specs here) that was generously given to be by another Arsian that does have ARC support (I think). The TV sitting in front of an old but nicer ...