The invention relates to interpreting the change in the increment of the RTP TS field as occurring either due to silence suppression for a voice flow or a change in sampling/frame rate of a video flow. By interpreting this change correctly, the value of the TS_STRIDE field in robust header compression may be correctly calculated leading to efficient header compression performance. In one aspect, there is disclosed a method of improving ROHC between an Access Network (AN) having a compressor and an Access Terminal (AT) having a decompressor, comprising providing flow information to the compressor relating to a change in the increment of an RTP TS field of a header; determining the change in the increment of an RTP TS field as occurring either due to silence suppression or due to a change in a sampling/frame rate; and taking appropriate action for TS_STRIDE.