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Round two audio problems on DVR

edders
12-12-2007, 12:20 PM
Am looking for suggestions to cure a problem with audio distortion and would prefer respondents have hands on experience with Dish hardware or good general sat knowledge. Come'on Experts know you are there looking for your input ;)

Our system: Dish setup about one year old have two 211 receivers and one 722 DVR. DVR is new, but problem was also evident with 622 DVR that was replaced/upgraded a week ago for unrelated problem (it was overheating and shutting off). Tv exhibiting problem is a 2 1/2 year old Panasonic TAU series CRT RPTV. Receiver location is fed by a single rf cable running from the satellite distribution block near the dish antenna, there is a newly installed module (see below) on that line and a splitter running to the dual tuner input of the DVR.

Problem: Audio distortion at some frequencies, sounds like poor rectification or noise from a microprocessor getting into the audio stream. It is a sizzling distortion apparent on only certain frequencies of the spoken voice, mainly of men like news reporters. This effect does not appear on our 211 receivers on our other two sets (HD LCD's) when tuned to the same programs nor did it happen on this tv with the old SD Dish receiver. Old SD non DVR receiver did not have in line module and splitter that was recently installed when we upgraded to the 622/722 DVRs. Dish also upgraded the distribution block near the dish antenna when upgraded to DVR. Problem is on more than one tuned station, satellite signals are in the 80-90's. Problem is evident on HDMI, Component, and line level audio outputs to our Stereo system. Am sure it is not a problem in the TV as it does not happen through DVD or VCR playback (component 2 and composite) and did not happen on old SD dish receiver. Audio problem was also evident at about the same level on the recently replaced 622 DVR, always thought problem was with that particular DVR unit (wrong). Again, distortion also evident when sat audio is played through SS Receiver using line level audio inputs. Am not utilizing video switching on receiver all input cables to tv are direct from the DVR to the tv. Video on tv is very good exhibiting no interference or dropouts on the screen.

Steps taken to resolve problem: Have relocated all wiring in system to make sure no ac cords are close to video or audio cables. Made sure no computers or rf transmitters are near 722 or on same circuit. Have separated ac circuits by running a extension cord so 722 is on one circuit and TV on another. Have tried several AC line filters in possession, not lab grade but of decent quality. Have tried running 722 off bu power supply with ac cord unplugged from wall, done same for tv. Have not tried any ferite beads inside of 722 unit or rf surppressors on cabling. Again, audio distortion problem occurs on HDMI and Component/audio inputs of tv and if using SR Receiver rather than tv speakers.

Suspect that the line of 622/722 DVRs have a problem with microprocessor noise getting into the audio OR that the "injector" the install tech put on the rf cable from the satellite to the DVR when we upgraded may be injecting some noise into the system. It might not bother people with less critical hearing but bothers the heck out of me. Again, other TVs and HD receivers sound ok to me, my hearing does not seem to be the problem. Would like to schedule a service call but suspect it would be better if I could just ask that the "injector" or DVR be replaced (doubt its the DVR as it happened with the 622 also).

What is the sage opinion on handling the problem? What is this "power injector" the service tech installed when upgrading the sd receiver to the 622/722 DVR and could it cause such audio distortion? This "power injector for the switch" as the install tech described it, looks like a laptop computer power supply with a cord running to a small module with rf in and out? Is it just an rf amplifier to allow one cable to supply the dual tuner input on the DVR? Can I work the system without it?

Ed in Consternation Land:eek: