You are probably having radio frequency interference issues between your Brite-View wireless video transmitter and your two Amphony L1600 receivers/amplifiers; they may be trying to operate on the same frequency bands. You can verify this by unplugging your Brite-view system from the wall and see if the crackling stops. If so, contact Brite-view and see if their system can operate on some frequencies other than the 5.8GHZ that the Amphony system operates on. The Brite-view web site indicates their system operates on 4.9-5.8GHz, depending on which country you are in. It your system is at that upper range, that frequency is already in use by the Amphony system.
Some newer WIFI routers "wireless-n" can also operate on the 5.8GHz RF band, so make sure any wifi routers in your house are not interfering with your Amphony units (just turn the router off temporarily to check this).
If your speakers are really inefficient, the crackling could be due to your speakers requiring too much power from the Amphony amps, but the likely cause is the Brite-view and Amphony RF transmitters operating on the same or nearly the same 5.7-5.8GHz frequencies. Eliminate the speakers as the problem source by temporarily connecting any small speaker or one side of a headphone to the Amphony amp's audio output connections.
I have been using an Amphony L1600 wireless transmitter/receiver dual amplifier setup for a few days. My system is working perfectly, with abundant power to drive some fairly inefficient Polk rear channel speakers (Model RT35i). In addition to great sound quality, both of the remote amps/receivers are running very cool, even though I have been driving them hard for hours as front channel speakers to evaluate sound quality and power capabilities.
I did initially notice a couple of very brief clicks or pops (a couple of times per hour; not very bothersome) but the wireless sound quality is very near CD quality with a large dynamic range (about 90db) and great frequency response. When I disconnected my 5.8GHz cordless phone that was about 90 feet away, all of the intermittent clicks/pops disappeared. I am operating on a 2.4GHz wireless network that is 2 feet away from the two Amphony receivers and there is absolutely no interference from that network.
My only complaint with the Amphony units so far is that both of the receivers must be within line of sight (no walls or windows, either) to the transmitter and can only operate about a maximum distance of 24 feet away. That is a far cry from the "up to 200 foot" range that Amphony.com indicates on its web site. I plan to check in with Amphony to see if that short range problem can be improved with an adjustment or with different units.
I have been looking a long time for hi-fi quality wireless units with built-in amps for driving rear channels and subwoofers. This Amphony L1600 is really working well for me so far. It is also very inexpensive, at $160-$190 for two 80 watt RMS amplifiers/receivers and a single stereo transmitter.
Good luck with your setup and resolving your problems.