BW(Sample Rate) Issue

[Rohith Rajan]

I am asking a doubt regarding receiver using an  Adalm Pluto SDR
In the receiver section we are using Polyphase Clock Sync, Linear Equalizer and Costas Loop.
My doubt is that is the configuration parameters of these blocks are dependent on the BW of the signal(Sample Rate)

Keeping the parameters as Normal  (In Polyphase Clock Sync block- No of filters(nfilts) as 32, Loop Bw .0628, RRC filter as

firdes.root_raised_cosine(nfilts, nfilts, 1.0/float(sps), 0.35, 11*sps*nfilts), sps as 4

; In Linear Equalizer No of Taps as 15 ;In CostasLoop Loop BW as .0628) when I set the BW(sample Rate around)1MHz I can receive the datas.

But when I set the BW(Sample Rate) as 125KHz I cannot receive the datas.

Anyone plese tell me what modification I have to make ?