On another occasion the Buddha explained his earlier statement that "whatever is felt is included within dukkha" to refer to the impermanent nature of all conditioned phenomena.
The changing nature of feelings, however, need not necessarily be experienced as "suffering", since in the case of a painful experience, for example, change may be experienced as pleasant. Thus all feelings are not "suffering", nor is their impermanence "suffering", but all feelings are "unsatisfactory", since none of them can provide lasting satisfaction.
That is, dukkha as a qualification of all conditioned phenomena is not necessarily experienced as "suffering", since suffering requires someone sufficiently attached in order to suffer.
- Ven. Analayo "Satipatthana: The Direct Path to Realization"
