An Obervation Of All India Radio(AIR) Gangtok on 4835kHz

As per my observation ,All India Radio(AIR) Gangtok has been often heard  with strong noise (hum type) on its shortwave frequency of 4835kHz(morning & evening) now-a-days.And this morning i.e.On December 14th .(2018) around 0123utc on 4835kHz the transmission was noted with free from any hum type  noise and there was music(Ram Bhajan-devotional song in Hindi by a lady) was on air.
Here is the link to the audio recorded:
https://app.box.com/s/u7cvrw3tiqwuh9didcohzttuiu0tf99w

But later around 0250utc during my air check on AIR Gangtok on 4835kHz , there was strong noise(hum type) and it was difficult to copy the audio contents.Though noise sometime became slighlty less.I understand this is due to some faulty parts in the transmitter.And AIR Gangtok goes off the air for a few days or so and again back on air  with no noise but after a while again the same problem occurs.
Here is the link to the audio recorded around 0304utc of AIR Gangtok on 4835kHz :
https://app.box.com/s/h7hgg8f4s7naqbvyrxgrk44exy12wuzf
(Audio Contents:North East News in English relayed from AIR Shillong,station Ids of AIR Gangtok in Nepali & freq. etc,next program-Nepali Modern Song Program-Music).
Special Note:All India Radio(AIR) North Eastern Service(NES) Shillong is not heard here on both 4970kHz (morning & evening) and 7315kHz(day) for several days.

RX Used:Grundig Yacht Boy 400
ANT:Cu WIRE 78' Length 30' Height With COAX LEADIN  

Geographical Location of Reception Place(Abhayapuri):
Longitude:26º18´20´´North
Latitude:90º37´50´´East
(For all cases)

More updates etc soon.
73s
Gautam kumar Sharma (GK)
(Abhayapuri)(Assam)(India)