so on my new 07 s/c, when i finish a call, the music comes back on then goes off for 2/3 seconds then goes back on again - normal?

also my tv gets good picture reception but the sound is intermittent - cuts out for 1-2 seconds every 5-10 seconds...

are these normal? 07 S/C in Java with Ebony

Not normal in my S/C. MY 2010 5.0 SC Galway green and sand interior!!
Have the Faultmate MSV2 Extreme to be tinkering with the settings etc. !!

The phone thing doesn't happen in my 2007 S/C, but the TV sound thing does... Past (too many to list, but a few favs)...
2007 Porsche 997 C2S Coupe
2007 FFRR 4.2 S/C
2012 Jag XKR 5.0 S/C
2014 Merc SL500 AMG 4.7 V8 BiTurbo (remapped to 560BHP)
2011 FFRR 4.4 TDV8 Vogue SE - Overfinch Conversion
2012 Porsche Cayenne Turbo
2018 AMG C63S Estate
2015 Mercedes GLE63S
2017 Maserati Levante Diesel
2017 Audi A6 Avant 3.0 Black Edition

TV is the same for me, phone isn't. 
07 Supercharged - Still breaking her in!

Boot soundproofing part 1 - http://www.fullfatrr.com/forum/topic15612.html
Custom exhaust - http://www.fullfatrr.com/forum/topic15296.html
18" wheels for Brembo equipped cars - http://www.fullfatrr.com/forum/topic15052.html

..actually, just re-read your post...my TV sound will drop out for a few seconds every now and then (like a couple of times every 3 - 5 minutes) but not for a few seconds every 5-10 seconds.

It sounds like a reception issue - have you tried parking in various spots and seeing if it's better / worse? Past (too many to list, but a few favs)...
2007 Porsche 997 C2S Coupe
2007 FFRR 4.2 S/C
2012 Jag XKR 5.0 S/C
2014 Merc SL500 AMG 4.7 V8 BiTurbo (remapped to 560BHP)
2011 FFRR 4.4 TDV8 Vogue SE - Overfinch Conversion
2012 Porsche Cayenne Turbo
2018 AMG C63S Estate
2015 Mercedes GLE63S
2017 Maserati Levante Diesel
2017 Audi A6 Avant 3.0 Black Edition

And the phone thing is definitely when you hang up only is it?

Reason I ask is that sometimes when I get a text or the phone does something that would usually be accompanied by a beep or noise of some sort, I'll get a brief mute on the sound system where the beep is / should be. Does that make sense?!  Past (too many to list, but a few favs)...
2007 Porsche 997 C2S Coupe
2007 FFRR 4.2 S/C
2012 Jag XKR 5.0 S/C
2014 Merc SL500 AMG 4.7 V8 BiTurbo (remapped to 560BHP)
2011 FFRR 4.4 TDV8 Vogue SE - Overfinch Conversion
2012 Porsche Cayenne Turbo
2018 AMG C63S Estate
2015 Mercedes GLE63S
2017 Maserati Levante Diesel
2017 Audi A6 Avant 3.0 Black Edition

I have the same TV sound problem in my '08 TDV8.

The video is fine but the sound cuts out for about 1 second every 20-30 seconds (on average - sometimes the interval between cut-outs is longer). This happens consistently & seems independent of location.

Has anyone had any luck diagnosing the cause(s)?