Weird Behavior of BPSK on RFX 2400

Hi guys,
I am trying to analyze the functionality of each of the blocks in the
mod/demod when I noticed the following behavior.

The high level modulator flow control is as | Symbols |-> | RRC filter
-> |amplifier | -> channel
and that for the demodulator is channel -> | Pre-scaler|
|agc| -> |RRC | -> |clock recovery| -> |slicer|

My understanding is that the real part of the output of the clock
must be close to that of the symbols or some scaled version of it(+a, -a
case of bpsk).

However, my observations (in the link below) show that the output of the
clock recovery depends a lot on the bit pattern, i.e., for the bit
1010 the peaks of the 1s and the 0s are way smaller than those of the
pattern 1111110000.

Since we are using a RRC I would doubt it is due to ISI . and since the
radios are close to each other and there is a direct LOS I donot think
is due to multi-path (or is it?). Is this behavior due to some
component on
RFX 2400/USRP or something else?


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In the clock recovery, the useful term in the output of the M&M error
detector becomes small for long sequences of identical symbols. This
affects the sampling instant, and I suspect is related to what you are
seeing. You can modify the gain_mu value to get these and similar