Audio Dropouts

[pjvent7777]

I’m a FIOS customer and I’m having frequent audio drops (of about a second in length) on one of my televisions (I have other televisions that work fine).  It’s a Sony Z9 connected to a Yamaha receiver (that’s a Yamaha RXA2060).  I’ve tried everything—different set-top boxes, changing out HDMI for optical, etc.  The only thing I haven’t done is try a new receiver (which I’d prefer not to do for obvious reasons).  My A/V guys are stumped and are pointing the finger at FIOS, suggesting that perhaps the signal strength in the house isn’t good enough.  So…I’m at my wit’s end here and would appreciate any help.  I also tried changing the audio output to L-PCM (and passthrough)…but that hasn’t helped either.  So, any help would be appreciated.