That said I think its worth considering other opinions, particularly from non Theravada sources.
Based on a recent exchange I had with Malcolm it seems the Sautrantikas/Darstantikas (as presented by the pre Yogacarin Ven. Vasubandhu in the Abhidharmakośabhāṣyam) allowed for at least tactile consciousness in the first jhana, because sukha is explicitly a tactile pleasant feeling born of tactile consciousness:
Abhidharmakośabhāṣyam pg 1233Vasubandhu in Abhidharmakośabhāṣyam wrote:iii. [Objection of the Vaibhasikas:] In order for the happiness of the first two Dhyanas to be agreeable bodily sensation, it is necessary for the person in absorption to produce a consciousness of touch {kayavijnana). And this is not possible. [Answer of the Darstantikas:] In the state of absorption, the body is penetrated by a wind born of excellent mental concentration (samadhi); this wind is a tangible which is agreeably felt (sukhavedaniya) and is called well-being. Hence there is produced a consciousness of touch (together with the agreeable sensation associated with this consciousness).
The opponents Vasubandhu is arguing against in the relevant passages take a position similar to Theravada, which is interesting, to say the least.
Regarding sound specifically, I'm not sure what his take is. But further down when discussing dhyana existences (not states in this life, but post mortem destinations) he says:
Abhidharmakośabhāṣyam pg 1240Vasubandhu in Abhidharmakośabhāṣyam wrote: a. In the First Dhyana existence, there are three sensations: 1) the sensation of happiness (sukhavedana) associated with three consciousnesses (eye, ear, and body consciousness); 2) the sensation of satisfaction of the sphere of the mind consciousness (manovijnana); and 3) the sensation of equanimity associated with four consciousnesses (eye, ear, body, and manas).
It would be interesting to see what Shramana Zhiyi has to say about this, since he was writing about jhana (dhyana) but I haven't read the book(s) yet.
Of course there is The Great Jhana Debate where you will find Geoff/Nyana arguing something that I think is similar to Ven. Vasubandhu's position