"Why the drop outs?

"I just installed the jvc hdr1 hd radio in my accord. I have the
antenna that is in the rear window.. I recieve alot of the hd radio
stations, but I am also getting alot of drop outs in my reception...
then it takes up to 10 seconds, sometimes less, to get the music
back.... I searched for some kind of antenna amplifier, but no deal...
is this normal for hd radio, do I need to buy a new antenna, if I am
receiving my regular stations fine? I am in NJ.. I get alot of the NJ
and NY hd stations which is the reason why I purchased it.... thanks
in advance..."

"HD1 should switch back to analog FM, this can be very very very
annoying if the volume level or timing is way off, but you should not
experience a dropout. HD2 and HD3 are subject to frequent dropouts
making their use in a moving vehicle more than annoying. Gerrrrr. Just
who thought this was going to be a practical technology since most
people listen to radio in their moving vehicles? I don't experience
these issues with AM HD and it does sound 100 times better than
conventional reception on today's poor AM radios."

http://www.avsforum.com/avs-vb/showthread.php?t=1022780

This inherently-flawed digital system is never going to work,
especialy in-dash!