RTL-SDR ghost signal at center frequency & hangs in GR spectrum view

Hi everyone, can someone explain to me, what the origin of the ghost signal close to center frequency is? It can be seen at [1] and [2] - both are EzTV668 with no antenna connected. It seems to me, that the higher the frequency, the more one can see the "burst-like" nature of this signal. Is this some mixer artefact from the E4k tuner? The best workaround is probably tuning a bit off the actual target frequency and using frequency xlate? Also, in [3] (german) the blind spot at 0Hz due to the coupling capacitors between E4k & RTL is mentioned. Is it possible to replace the capacitors with 0-Ohm resistors to work around this issue, or will this cause other unwanted side-effects? Or does this make no sense at all since one should always tune a bit off and use xlate due to the ghost signal? I guess it should also be possible (w/ some hot glue & wires) to insert some jumpers (like OsmoSDR) instead, so one can use the ADCs directly for LF/MF with some extra analog stuff? Regarding the OsmoSDR source - I also gave the RTL-source from gr-baz a try and noticed, that with averaging enabled in the spectrum view in GR, the top-block GUI usually won't react to user input any longer when using OsmoSDR, but this doesn't happen with the gr-baz RTL source, although I used the same sample rate in both cases. Does anyone understand why it doesn't hang with the gr-baz source? Thanks for your answers! Regards, hunz [1] http://hackdaworld.org/~hunz/rtl-sdr/wo_ant_2m_osmo.png [2] http://hackdaworld.org/~hunz/rtl-sdr/wo_ant_70cm_osmo.png [3] http://www.mikrocontroller.net/topic/253371#2610540 -- Benedikt Heinz hunz(a)jabber.berlin.ccc.de